If you just need a single server that you don't care about then it's way cheaper to just own it yourself. You probably don't need 99.999999999999999% guarantees for your data, but if you're a bank then you do need those guarantees because losing all of your documents would be disastrous.
Normal people aren't worth anything to them. A company might spend a million a month with AWS, to get that with normal people you'd need at least a hundred thousand customers. And those people are going to spam you with tickets and do silly or illegal things. They're just not worth it. They obviously won't turn money down, but it's not a growth area for them.