We were taught not to fill it up full because it could cause issues, so we always filled our M-16's two rounds less than full. Someone who didn't know that could certainly make the mistake of filling the mag full, and then have issues, however, they could also fill it full and not have issues. It isn't 100% of the time that you'll have issues. I honestly wouldn't know how often we would have had issues with a full mag, because we just never filled them full.
Free market capitalism isn't right for America because it works better. It's right because it's free (and it works better).