I used to bake a lot years ago, but I usually didn't eat what I made (too much product) so I would give them to a friend so he could share them with his coworkers. I once commented on being happy to bake new things and have someone to give them to, and Friend said, "Gee, it must be nice to use my coworkers as guinea pigs" (my baking was perfectly fine). I looked at him and said rather evenly, "If you feel that way, then I won't bother making things anymore that you could give to them." I never gave Friend baked goods again (I kept baking; I just gave my baked goods to other people). Friend did still get to partake of my cooking and baking over the next few years but never received any batches of anything from me again.
Another time, Friend asked me to design a website for him. I told him I didn't feel like it. Friend then said, "Gee, for someone who wants to do this for a living, I'd think you'd jump on the chance to do this." Again, I looked at him and said in an even tone, "You're right; I DO want to do this for a living. If you want me to design a website for you, then you need to pay me." Friend just gave me a look. Never heard about it again.
I haven't seen "Friend" in almost three years (the last straw was when he got pissed at me because he thought I should hold him as more important than then-DF).