In the real world, people with silly names happen in to them, sometimes by accident, sometimes because their parents are idiots, and sometimes because of language. (I'm looking at all the Gaylords, Fuggers and Wangs out there.)
In writing, the author picks and chooses the names. You don't get to excuse yourself out of it by going, "well people in the real world have silly names," because it's quite literally not the real world.
But w/e. If you want Staff Sergeant Max Fightmaster or Rad Heroman to be your guy, then he's your guy. Though at that point, you could at least go for something that actually sounds badass, and not selfaware silly. Though any attempt to sound badass will sound silly on it's own, or cliche. Like Clay Rockfucker or Slab Grunter.
You can always just go down to the local graveyard/google the local dead listings and look for names that sound good.