while they may not ban directly for money it is part of it.
-Riot says you do not own your account which first off is big BS (blahh blah blah you agreed to these terms)
-you are not compensated for your banned account which is a big FU, because you can spend hundreds of dollars but not get a single bit of reinbursement. If it was not about money then they would offer some sort of reinburstment it doesnt even have to be full, but why should they care you can either A make a new account or just deal with it.
- Riot would not Auto ban accounts if it affected their money I can guarantee you that, but the fact that it can only increase their revenue is why they do it.
if you don't think its about money just imagine if banned accounts if it cost them a single penny I can tell you for sure they would not.