It appears as if there is a will there is a way. According to a post on the forums players are able to trap incoming players in hostile situations. It goes as follows:
1.High level character creates NM/Norm game in Act 1.
2. Character grabs champion packs and elites and trains them to town.
3. Player enters into a house and makes game public.
4. Player AFK’s and watches players enter into the game to their demise.
This is possible due to the fact you have no control over the game you enter and towns are no longer safe zones. Until Blizzard ( and that’s a big if) fixes this that quest you choose to group on could be a friendly crew about your level, or a level 60 with a chip on their shoulder. For now it’s best to play with friends, and if your lacking those try our Hardcore forums!