Emily,
I tend to treat requests as legit when approached, but if something doesn't seem right, check it out. Ask for the station. Margaret, Kate, and I have a policy of only sending out 10 percent of a run a free promos, everything else, we pay ourselves back at our retail price. That limits the number of recordings we give away, and makes sure that the money's in the account when it comes time to do another run. Doesn't do the personal pocket book much good. But otherwise, you can find reason to give all your recordings away, if you don't have some blocks.