MG shooting ground is just visual, it's actually shooting at the infantry. Also, every single starting weapon crew has garbage weapons that can't damage anything, it's not limited to MG42, the only thing bad about MG42 is just that it sometimes refuses to shoot(but this probably happens to any MG, you just see it more with 42 because it's used more)
Please, Riflemen were complete garbage (and they still kind of are). You have to spend 150 MP/15 fuel and 120 munitions just to stay ahead of Volksgrenadiers. Anyone who says Riflemen were good never played USF.
You like saying non sens both of you, do you? USF tier 3 is a building and if you take it down, guess what, you can't build anymore units from it.
What you're comparing is if by some mechanism it would be possible to destroy swerer's canon and need to pay manpower to rebuild it on top of the T3.