Sure... you can dress like a mall ninja, play by your big boy rules, add another gizmo to your rails, fine. Done safely, "training" can be fun and informative. Feel free to run 'n' gun to your heart's content. It's your time, money, and in the case of those idiotic downrange drills where you rely on the competence of complete strangers, possibly your life.
But remember...a couple of weekend tactical carbine classes isn't practice. It's playing.
You'd be better off honing skills you might actually use.