I live in a very cycling-aware area and this is a frequent problem for me. While I appreciate the fact that they're not trying to run me over, it really boils down to the same problem: when you ignore the rules, it puts everyone in danger. We have a fair number of whoever-gets-there-first 4-way stops and it becomes very confusing for the other 2 cars when the first car in line waves the bicycle through. Ambiguity is never a good thing when it comes to intersections.

That all said, I really do appreciate not being run off the road.