I only play zombie mod with servers that have unlimited ammo. Although the unlimited ammo can be a pain when someone is barricaded in a room.
yeah i used to do escape maps like boat escape space station escape used to be fun because by time you get to the end of the map the people who actually fought and died are usually the 'noob' zombies and the guys who survived are either very lucky and willing to fight until your boat/ship/helicopter leaves or actually had skill and know what they're doing and want to work as a team.
other maps were just fun with the barricading bookshelfs and chairs and stuff against the wall and blow the heck out of the zombies

and yes it is annoying and im usually that guy xD