What about you getting invited to a guild and accidently accepting while chatting?

No i reject this change in game mechanics. Last chaos community thrives on some drama and spying too, for those that still can muster it. Go for it haha

P.s. And consider all guildless crossy noobs if this is implemented

( sorry for my non perfected english )
Guildless Crossy Noobs? Such a thing doesn't exist! Everyone wants the Crossy!

Supposing though, that someone just needs locking for a few days, while they do SP farming? Also, it may be wise for all guilds, to have a guild rule forbidding begging.
Most guilds already discourage their members from begging for stuff, whether from their guildies or from other people. That won't help at all tho, if you can't punish said person for breaking said rule due to the 10 day guild lock after a newbie joins you. Also, if they just need exp lock for a few days, then there is this thing called "asking nicely".