Trash, especially 1lb lp tanks put in holes and then frozen in. General rude people.
As far as claiming ice territory, if I'm new to a lake, I'll have already done some investigation of furoms such as this. I'll ask what end of the lake, best baits etc. When I get to the lake I'll go to the area that was recommended, if people are fishing the area, I'll say hi and start the general chit chat. If there are open holes I'll ask if they have a claim on them, if not I'll save the edge on my auger and fish. I do enjoy fishing with others, but then there are times I enjoy being out there solo. Either way it's all about being polite and respecting others.
If I head out to fish a lake that I know, I'll go to the spots that I know have produced in the past. If I get there and someone is fishing, I'll say hi and mention how good it was here the other day..ect This one particular area can have alot of people fishing closer than most would care to have(15/20feet), but those of us that fish it know what the deal is. There are even times that I fish this area that I'll cut extra holes because I anticipate others showing up, this eliminates the need to make noise and I could care less. Heck, if I hadn't figure out what they were hitting on and a guy next to me was pulling them out, I could say "OK, I'm dying over here, what's your secret"... that proved to be the day I learned that the tiniest possible white moonglo was the ticket and that the 4lb line I had was too heavy.
Bottom line is impolite people, people who don't take responsibility for thier dogs, and as said already, people who leave fish on the ice that could have been thrown back down the hole. I can't understand when someone says "Sorted through 200 fish, took 50 and left the rest on the ice"
As far as those who have phone call issues...leave the song "gone fishing" as your message, turn it on silent or vibe, answer the calls you want, let voice mail take care of the rest.
OH, one last thing...running out of bait and propane when the bite finally turns on!!