So I have to keep a voucher to repeatedly play the music I paid for? Sorry. Once I've confirmed the CD plays correctly the sales slip goes away. No need to be harassed.
Practically, this is only a problem if you lose your e-mail address. I don't even have a Bandcamp account, but it remembers that the same e-mail address has been used to make all of my purchases, so I can re-download anything at any time even without an account. Though I prefer to just keep local backups of all my mp3's.
"Religion is something left over from the infancy of our intelligence, it will fade away as we adopt reason and science as our guidelines." -- Bertrand Russell