I thought you hit 30 o-o; you don't have a jungler every game?
Not always. The group I play with isn't very fluid in their chosen skills. Out of the 11 of us who play together, I'm the only one who can manage support without fucking it up, and only one of them is capable of jungling. So we often end up with a 2/1/2 format. Occasionally it ends up with 2 adcs on bot, so I take on a more offensive role than usual on top to make up for the fact that bot usually gets ruined really quickly. The only real upside to having two top is that ganks are less of an issue; unless the enemy team has good communication we can usually split up if we know a gank is inbound, which turns into a kill for us because the jungler hasn't got the chance to react.
But yeah, lacking a varied team kinda sucks... I can perform any role aside from jungle, and I'm learning that now, so I'll be able to fit any remaining role. Especially in ranked, where I've encountered quite a lot of insta-lock/premades who are, for lack of a better phrase, fucking retarded. Blitz/Malphite top? ok... Had someone take Soraka mid, didn't work out well at all, though fortunately that one wasn't ranked so no big deal.