Lol that's a wild concept. $5 for 300 searches... so now when I go down a rabbit hole I have to count my searches.
Also, that gives them perverse incentives. If they make searching just a little frustrating they can get more searches out of you = more money. That's not right.
My take is they're a little more cautious than full Arch. Arch will just push stuff because it's "ready", Manjaro does at least some testing so I'm not the guinea pig.
I don't have any issues with AUR stuff though, everything pretty much works out of the box.