I have found that people have the morals they can afford. If you think you are losing money by not providing your traffic with those links and you're ok with that... then no problem. If you NEED to make more money (to do things like pay your rent/mortgage) I think you might give them a test to see if they make you money
If you're not comfortable with something on your site then don't promote it. But for a majority of people if it brings in cash and it is legal...no issue at all
