OK, I've got it...now let's see if I can explain this. If you post a quote in GTP Lite, it will show up for everyone inside that default template. This is because vB3 saves post's vB code as HTML when the post is saved (instead of converting it every time a post is displayed).
I've changed the template now for GTP Lite so that it's the same as the main style. I doubt that old quote's will be converted (since they are already saved wit he old HTML in the database), but this should prevent this inconsistency from appearing in the future.