Ok, folks... Forget about the "why"... Who cares why? As long as I can get some free miles, then I will consider it. I know for a fact that certain merchants will do this, no questions asked. Of course, to make it worth it, I would have to buy and return, say, a laptop PC for $2K, or even a diamond ring for $15K (can't go higher due to credit limit, doh!). Doing this over a 2x/3x mile promotion (e.g., Delta Am Ex card) would be even better.

Regarding the schools, I did it a couple of times when I was young and naive. Now, I go after the big corporate dogs with profit to burn.