For me it is when companies/services market themselves as donating to XYZ cause if I buy their product. If they want to donate, they should have already done that with the money they have. Asking me to give them profit so that they can donate is so obviously pretentious.
One time a guy convinced us to spray for spiders. My wife hates spiders, and ants, and bugs in general. So the guy came and sprayed for bugs, and sure enough, all the bugs in our yard were gone. And so were the birds, the bats, and the squirrels and the bunnies. It took a long time for them all to come back, but now my wife tolerates bugs as long as they stay outside.