I'll sign the petition, I prefer scrounging/collecting/looting ammo to just having an unlimited supply of it.
Ammo's really more of an issue in real life where you fire away 120 rounds under a minute flat, realizing those were your only four magazines and now you're effed. As most combat in games tend to be at 3-15 meters, not to mention you just point and click, ammo is usually quite abundant (in any game that has a semblance of realistic damage from firearms).