I'll retract my previous statement; tanks and other mil-spec gear is not the kind of thing your average shadowrunner is going to go up against, so it doesn't quite make sense to compare civilian equipment with military gear.
And you don't bring civilian gear to a war zone, so if you're going up against tanks chances are you're prepared for it.
The power creep is only problematic if you pit civilians against military operatives, and at that point it should be unbalanced. An M72 is not an FGM-148, and I'd liken the Aztechnology Striker more to the former than the latter.