I must side with AJ3042.
If AS wasn't losing money from this, they wouldn't be auditing and shutting down accounts left and right. We might not know the exact contract that they have with BofA, but obviously one of them is losing big money from people churning millions of points. So either BofA or AS is losing money, but we do see AS is the one doing the auditing, so it's likely them losing the money.
If BofA is losing money, they might be forcing AS to audit, close accounts, and clawback miles for them to continue their existing deal.