I've always felt that SG and PJ were close buddies, STP and Alice got to be better friends over the years and Nirvana simply hated everyone. I think bands not getting along is kinda cool to be honest. It's fuckin' rock n roll baby! I love both Soundgarden and Pearl Jam and I don't feel different about them for "trashing" STP (I still want to see some quotes of this). There's a lot of egos going around with those early 90s guys. They each think their band is better then the others and they should. They're rock stars. Some just won't say it to the media.
STP reunited for many reasons and, yes, money was one of those reasons. Dean admitted in an interview and Scott called STP "commerce" in another interview so it's not like it was some big secret. And what is so wrong if someone (band or whoever) tries to make money? The MJY demo had a variety of styles in it (funk, rock, country, etc.). If I was young and broke and a record label said to me make more music like these 7 songs off your demo I would say fuck ya I will. That make me a sellout? Maybe, maybe not. Greenday as another example (not a big fan of theirs) were pretty much made outcasts in their home town because they signed with a major label and "made it." Some people think that if you earn money making music and get famous by it, you're shit and become "sellouts." It happens a lot in the metal and punk scenes.
And if the SG camp all say money was not any slim part of their reunion reasons then they are lying. I read in a few places that Kim of SG is broke and basically homeless, that they were given very nice offers to reunite after the Cornell new years tweet, and that they aren't really planning to record more then one song. One might think that the timing of this SG reunion isn't just to remind the whole that SG is awesome. They do have a greatest hits, DVD, and video game coming out.
And for the whole flame wars by message board fans... SG and STP are completely different - sound, style, everything. We can all agree on that. We also can all agree that every message board has fans who will attack anyone who talks shit about their band. That's just the way it is.