Is there any reason in the world to have an emotional response to software other than spending money for a product that didn't do what it claimed to do?

Yes.

I think part of the reason people get so worked up over this kind thing is that others' choices do affect you. Which program "wins" will determine which one gets support. No one wants to end up owning a Betamax in a VHS world.

Anton's post says it all: the once unified Poser community is on the verge of splitting, with D|S/Bryce going one way and Poser/Vue going the other. There may not be enough customers to support both. Naturally, people get emotional.