As we all know, businesspeople are morons that try to cheat you all the time and shamelessly enrich themselves if they're high enough in the food chain. While this is despicable in a way, it's not as bad as it sounds as you know what to expect and it makes people a little more predictable.
In fact, I have the impression that one of the most significant problems in our nice capitalist world isn't the greed and cheating – people and in bad cases even the law seem to be able to deal with that – but rather what I'd call a hidden agenda that people pursue without owning up to their opinions. 'Business reasons' frequently just seem to be given to cover up for those additional aims. While these days people can't get away with saying that you won't employ women 'because they should be cooking', a business case is made of the risks of a woman getting pregnant and not being able to work for a while yadda yadda yadda. Similar examples can probably be found for whatever ethnic group, religion, lifestyle people just don't happen to like. In many cases the 'business reasons' for not employing them – even if they're true – seem to be an afterthought to the 'Nope, don't want that here...' knee-jerk reaction.
So in a way, the fact that many people aren't real business people, who're totally after their bottom line, but they're rather following some kind of unclear (but usually conservative) agenda and only invoking 'business reasons' if the need for giving objective-sounding justifications arises, may be a bigger problem than those people being businesspeople in the first place.
I've carried that little theory around for quite a while now. It was triggered once more these days as we're looking for a new place to live in. More precisely, it's four of us, aged 26 to 31, all with university degrees, doing our PhDs or working. And mind you, this is a university town and it's the 21st century. Still, many landlords absolutely want to rent out their flats to families only. Just think about that – I don't think it makes any business sense: While every single one of us isn't earning huge amounts of money, together we have more money than most families. We're even prepared to pay a little more. In addition we don't – and won't – have any little kids around that seem to require that peculiar balance of silence (
Pssss, little Karlheinz needs to sleep now...) and noisyness (
Look, Karlheinz can run around all by himself) as well as rubbing baby oil into carpets and wallpaper (I know I did) and other fun things. Add to that that in families it is much more likely that they go broke or spawn more kids and need to move out, to a bigger place – in fact the main reason why people moved out of the flats we looked at.
I am not saying that people shouldn't have kids – it's a free country and some people even think people should have more kids – or that people shouldn't rent flats to families – still a free country, you remember – but I don't think there's a good business case for preferring families. So all the people who do should own up to their prejudices and stop pretending they were businesspeople.
Strangely, the landlords who seem to be most comfortable with shared living arrangements as ours are either the really big and evil ones (lots of business sense there I guess) or the really unprofessional private people who rent out a single house (common sense, perhaps). Those don't want to send a message of any kind, they just want to earn some money on the houses they own having as little trouble as possible on the way.
Maybe you’re being lumped with a category unfairly. My wife started a company that has four rental properties in a college town. For one year or so, the property manager (who was admittedly not really doing a very good job and ahs since been replaced) rented to college students. The tenants constantly violated terms of the lease and utterly abused the property (including knife throwing practice into the wood siding of the house!). Now, if we had one rental and were her to manage things ourselves (like the single house rental you mention above) we could interview and deal with college kids. I guess it is our fault for being absentee landlords but we invest a lot in keeping these properties in good shape (in fact I don’t think that they have made a profit yet) — we won’t just “let them go” and become slum-lords.
To begin with we’re obviously not your rowdy bunch of 17 year olds, looking for a flat to trash. And we are trying to make that clear right away.
The case you do describe will probably just make a good ‘business reason’: The college kids will lower your profit or even do permanent damage to the property . But that’s not what we experienced - and the point I was trying to make -: people just said nope, don’t like their style of living, completely disregarding that we are probably even better business than many other tenants.
Of course anybody is free to do whatever they like, but they shouldn’t lie. Which in this case would mean pretending they’re doing business while they’re actually just being righteous. [And I find it enraging (on good days: funny) how people can be so square. These aren’t the 1950s.]
 While the knife throwing you describe may be extreme, there seem to be viable models to rent out property to ‘college kids’. Just charge €20 extra per person and month. And for four people you’ll almost have €1000 extra per year to cover for additional (non-destructive) wear and tear.
Another anecdote: My parents are renting out the house we inherited from my grandma. It’s in a small village and it’s a very pretty 300 year old half-timbred house that we had restored (hellishly expensive, apparently) in the early 1990s. People living there included young couples (with children after a while) and pensioners – probably the demographic preferred by those conservative landlords. And all we had was trouble: people being in debt, not being able to pay their rent. Children making a lot of noise (which is ‘shared’ among the flats), causing endless bitching of the other tenants. A flat needing to be completely renovated because it was much dirtier than any flat I ever moved out of &c. Probably having a few college kids instead would have been less painful. Unfortunately there is no college nearby…
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