Yeah, it looks like the Baits has some limit .. Yesterday, in my 2nd main account, i drained up my 330 stamina sweeping plots and elites, that whole 330 stamina sweeps drops baits but my Free Keys for the Time-Limited Ninja Recruitment is not yet complete so i used 2 Normal Potions to have 100, that 100 Stamina or equivalent to 10 sweeps didn't drop a single bait ..