I believe it will take fucktons of gaccounts to game the system through +1. It may not be possible at all to effect serps for people that aren't somehow connected to these accounts.
If that's the case, the only way a +1 package can be sold in SBT (that isn't a complete ripoff) is for the seller to have POPULAR, INFLUENTIAL gaccounts networked with lots of other people, REAL people out there. -Which of course is hard to prove that they have. Much like proving you have a big email list of real buyers.