This is a bit like arguing that one shouldn't be punished for a traffic violation because not every other potential offender got caught.
EDIT: The difference being, Apple says YES / NO to every app, and every app always goes through the process, unlike policing traffic violations. If Apple is not being inconsistent, they need to say why.
Either way, in this case they blocked a developer that was making what sure as hell looks like spyware to me, I'm not convinced this is a bad thing.
Also, you absolutely do need a license to operate a car. Probably not a good metaphor for your case.
I personally think all such apps should be blocked. What bothers me is the inconsistency, or the opaqueness that means we cannot determine whether or not there is an inconsistency.