Yeah, there's no need to take up an entire room if you want to solo @-@; And I don't think anybody needs to take on that 1927462 mobs in just one room.
Besides, if you're soloing, yeah, why would you want a room anyways? You really don't need to burn all those extra pots and stones @-@; When I solo, most of the time I go to a corridor and drag mobs by myself.
But then again, there are some people that are not so nice about sharing rooms o: I was with a party once, and we came to a room on the other side of another party. All of us went "oh, room taken," and prepared to go away when the other party went "someone else is here, kill them" = =;
But we ended up going to another room and getting all the mobs there, LOL.
edit
Oh yeah, this isn't in the battlegrounds, but there was somebody hogging a spot in GC today o: She would tell everyone "go away, my partner and I were here for 2+ hours." If we didn't, she would grab a train and head for that person, saying "alright, I'm training ___ (insert person name)." She couldn't get rid of the train anyways = =; And once when she actually DID get the train off on someone, it was on a 5x fighter that finished them off pretty easily.