I think most merit sales generally stick out like a sore thumb. For example, whenever I see someone with one merit and 1000+ posts, I assume they bought their single merit.

I am not terribly concerned with someone buying a single merit. Someone ranking up to a junior member isn’t going to hurt anyone.

My guess is that they want to avoid having to wait 6 minutes between their bounty posts.

Note that this does not affect:
 - PM rate-limiting, which is based purely on activity & whitelisted status.
 - "You must wait ___ seconds...", which is based purely on activity & whitelisted status.

Maybe Theymos could offer a lower version of a paid membership that is less expensive than a copper membership, maybe it could be called “bounty spammer”, cost $20 (in BTC) and give those who are wearing it the same abilities that a junior member has.