Respect can be earned and taken away pretty quickly I reckon , I take each session as it comes that dictates how I react to drop in's etc..got a few basic rules that i follow, I try not to be too petty.
Drop ins happen for a lot of reasons and blowing up is sometimes not as effective as just showing genuine disappointment or asking "what happened there mate?" , once the apology is given I move on, if its not then I just go by instinct from then on.
I have accidently dropped in before just cos I was frothing and literally didn't see the guy on the inside, always apolagise face to face and make sure it does not happen again, usually does the trick.
Sometimes if there is just too many idiots out there i just move on to another peak, I am out there to have fun not get in a fisty cuff, that's what my mates garage gym is for