[StevePerkins]

Heh... have a bad experience with lunch-n-learns at a previous gig? :)

Pretty much everything in this comment thread describes approaches that only work with the buy-in and support of upper management. If OP (or anyone else) is truly in a position where code reviews are impossible, and lunch is everyone's "one break in the day", then there is very little you can do improve code quality in that environment.

In THAT kind of environment... you slog through, get what you can onto your resume in preparation for the next job search, and don't let yourself get too emotionally attached. Support for quality has to start from the top, you really can't "grassroots" it if upper management pays only lip service or doesn't really care at all.