So probably those images would be OK on Australian television. But its not Australian television, is it?
I guess the pink elephant in the room is that this a predominately male conference (actually not sure of this; just making a well-educated guess). Even if thats not the case, I think "workplace rules" should be implemented at such events. It is a bit difficult to think about: for instance sexual harassment of this kind usually implies some sort of on-going problem. But LCA is a on-off thing. However there certainly is plenty of continuity between open source and the open source conferences (I always see the same people all over the world) and we should endeavor to make it a welcome environment for everyone.
So really I don't see this as about separating people into the offended and the offenders. The problem isn't so much about people feeling offended; its about the awkward situation it creates. Its ultimately about creating the culture that we want to be.