You CAN just pretend you're not hit. Airsoft runs on the honour system - But we have marshals to look out for folk Kevlarring, and will shadow anyone suspected of doing so. It's just like any other game or sport, you can cheat, but you're ruining it for yourself as much as others.
It's just that cheating here generally involves rising levels of pain until you finally admit that the BBs are hitting you.
As for the shotguns... They're bloody good fun!
If Airsoft was purely about winning, and hosing the most BBs as possible, everyone would use the smallest rifle possible with the largest magazines possible.
What's more satisfying? Firing off 600 BBs in one go to get a kill at long range, or knowing that you're good enough to get in close for a shotgun kill... Then blasting your way back out, knowing that you only have 8 shots left til your gun's dry?
Some shotguns fire 3 BBs in one go, and fire 10 shots from one "cartridge", which then needs to be manually ejected and replaced.
Some are even more realistic, and fire up to 10 BBs per shot, but hold 8 cartridges of 10 BBs each and ejects one cart with each rack of the pump.
Then there's the gas pistols with moving slides, and bolt-action sniper rifles
