You're right...but you know what? I'm very fucking close to boycotting every single shooter that uses this kind of rank up/unlock mechanic from here on out. If that's every shooter from here on out, oh well.
I definitely hear ya. The frustration of feeling comparatively gimped to everyone else is not fun in the least. I'd hate to try and come into something like this game even another week from now... let alone months down the road.
I don't think it's going away any time soon though. Continually having to "get the next thing" is just far too addictive for most people, and the game companies know it, and they know it'll keep people playing their shit far longer than if they gave you everything up front.