"caring only about money" is absolutely a political ideology. Although I agree that it's weird to label this as liberal, as it's an ideology that's usually closely aligned with conservatism.
As for the "weirdness" you refer to, the company was arguing that banks indeed do not care only about money, but impose costly political agendas too. Hence the supposed value proposition.
Chasing personal benefits is also an ideology! One in opposition to the ideology that suggests we ought to work for benefit of others as well as ourselves. As is the idea that people's "basic instincts" are to chase personal benefits is too. If you don't believe me, try hanging out with a small child (under 4) and see how selfless and generous they are.
What if the banker considers those choices made in financial self-interest to be against their own personal ideals (of being selfless etc) but did it anyway?