Several things don't make sense

All that stuff was mailed to his Dad's house, you see that in the beginning of the movie.. When it's all said and done, it was about robbing the bank goes money, and nothing else.. He's not really following an ideology that he's preaching

His motives were rather confusing. Originally, Bill seemed to be plotting the rampage for political reasons. When talking to his friend Evan during the beginning of the film, he was almost trying to normalize and defend capitalism, but then he eventually ends up hating capitalism all together later throughout the film. Specifically, hating materialism. It was a really mixed message. His nihilistic point of view about overpopulation only adds to his reasons. But honestly, I don't think Bill had a suffice or confirmed reason why he wanted to kill people. I think he was just an angry and bloodthirsty person. But then again, Bill also seemed to have a lot of financial issues, or at least unfulfilled financial desires (which is part of the reason why he hated capitalism) - but then he ends up going through great lengths to rob a bank...which pretty much makes Bill the ultimate hypocrite. I'd say 95% of Bill's reasons for engaging in the rampage were all about money. The rest of the percentage was him simply killing people. He operated on a really imperialistic point of view. He took what he didn't have. Along with taking other people's lives. All in all...Bill was one scary dude.

Been a while since I've seen the movie so I can't remember if he eventually revealed himself or not but wasn't the entire thing just him putting on a show so that he could frame his friend with fake motives? So everything he said and did was for the benefit of disguising the perfect slaughter and robbery..

I'm not smart enough to completely understand these movies, and therefore they don't make sense to me, because, yes, he does seem contradictory to himself / his goal, but maybe that's intentional, since he's not stable, regardless of his message to society. Anyway, changing the subject to the money issue (by the way I never understood the ending of the first movie because there would have had to have been 2 bags of fake cash, one of which would have had to be flawlessly counterfeited, for everything to work), I never took the fact that he robs places as him being a hypocrite. I just figure he robs places simply because he knows he'll need to buy tons more ammunition, grenades, cell phones for his bombs, etc. (from where or whom, I have no idea), and that takes money. He never seemed to use the money for anything elaborate or fancy (I don't think we ever see him eat or drink in the second movie, do we? He seems to live on cigarettes).

I saw it as his primary goal was making money, due to his family wanting him to move out, and him being sick of eating at crappy fast-food places, and having to buy crappy coffee from the crappy coffee place, but he needed to go on his 'rampage' so that it looked more like his friend that committed the murders rather than him. With that, he also had a 'reason' to kill people that supposedly 'wronged' him.

I think the political stuff was all just a front, again to make it seem like it was his friend that committed the murders and stole (then 'burnt') the money.

Bill's video, that we see sometimes through the movie and then at the end, was maybe just a half-hearted attempt at giving political reasons as to why he went out to kill (which subtly probably meant "too many people in the world = I can't make enough money to live a good, comfortable life because they're sucking up all the resources, making things more expensive, etc."), but again, his primary reason was money, imo.