Modern Warfare 2 Question?

Why do people that use the FAL get called "modders" by everyone? I love the FAL because of its accuracy and its conserves ammo good too. Every now and then I'll be in a match and someone would complain about me shooting too fast and say I have a modded controller or something, which I do NOT have. I tell them if you have a quick trigger finger and a good aim you'll do good with the FAL. But this doesn't change their minds. What do you think?