I just did a quick dig through the DB -- looks like ~60% are using that first stamp (or two, if they live outside the US) to mail something to themselves. The remaining ~40% either don't use those stamps at all or they send a letter to someone else.

As for the picture of the paper/envelope, (this is probably going to sound dumb) but I can't figure out how to take a decent shot without making the stuff look terrible. Any tips or thoughts on how to get past that?