1. That is exactly what class actions are for, because small damages multiplied by many people are big damages.
2. That's also why we need punitive damages, so someone can't get away with unlawful actions by deliberately coasting along under the threshold where it makes sense to sue. For instance, IIRC, you can collect something like $5000 from someone who doesn't put you on their "do not call list" when requested. That amount has nothing to do with the value of the "few minutes of your time it took to" answer a telemarketing call.
But was it worth it?
Multiply this across all the fraudulent job postings, and it really starts to add up.
It's clear (to me, at least) that we need better laws to handle this sort of wide-but-shallow attack on people. It's analogous to spam.