They are deliberate cheaters. Simple rule is if you feel or hear yourself getting hit stick up your hand and shout hit. It doesnt matter where it came from or who fired it a hit is a hit. To not call it is cheating.I have encountered malicious cheaters, even overheard a couple of lads plotting to tell the marshalls I wasnt calling my hits because they were getting annoyed that I kept getting them. So after shooting them in the bony bits I went and informed the marshall myself. Airsoft is no different to any other part of life you always get a tw*t somewhere, just got to learn to rise above it.
Or at least how to punish them in a non rule breaking manner 😈