When USF captures vehicle, they still can use vehicle crews for it.
When someone captures USF vehicle, they don't have vehicle crew.
Damn, its almost as if faction trait doesn't magically go away from the faction, just because they picked a toy that isn't originally theirs, nor other factions can inherit magically faction traits that aren't theirs to begin with.
There is nothing wrong with that.
You are free to have whatever opinion on the subject, but it doesn't mean there is anything wrong with the mechanic.
And when OKW capture vehicles they have 3 vet while when other faction capture okw vehicles they have 3.
Now if you believe that soviet captured weapon should have 4 men crew while other faction crew should be 6 men try to come up with an actual argument explaining why soviet need this advantage.