I have been approached here recently from someone I had no contact with or connection in any thread that I could find, asking for fabric. It kind of turned me off.
However, I also responded to an offer for a trade and had a couple of people contact me offering to buy or barter fabric with me, to build their stashes. I have no problem with that. I sent one lady a whole bunch of strips and bits, and she has responded both with photos and emails to me, and on the board. I didn't charge her anything and it was a joy. Another person here I know is going through a tough time and I sent a care package. Again, it's just paying it forward.
I'm kind of with jamh on this- if I have a bad feeling, I don't participate. If I send stuff, I only worry about my own motives, and let go of the other person's. If I get used occasionally, but help honest people along the way, that's fine with me.
I used to live near a rough section of Phoenix/Glendale, AZ, with lots of panhandling in the grocery store lot. I got into the habit of buying extra beans, rice, and a couple of boxes of mac and cheese. If you tell me you want to feed your kids, I'll give you food- not money for drugs.
I only have to worry about my actions. I believe in the long run, the universe settles the score.