Though I can't comment on whether on not that idea's doable/practical it does seem like an awfully simple solution .... which is problee why it isn't done. Governments seem really great at overlookin simple fixes and instead choose overly complicated schemes to meet their needs, most especially when it's an expen$ive option.

Governments seem much happier blowin money like a stripper after a really good night at the club than spendin it wisely, which like in the case of the stripper, was actually someone elses $$ to begin with