I fail to see the equivalence. These are just loans with weirdly favorable terms. If the other bank had shareholders, then this would be a breach of the fiduciary duty. Otherwise it's just bad business? Bad business != fraud.
I'm not sure why would that be fraud - who would be the defrauded party there? Offering wildly different conditions or prices to different customers definitely isn't fraud.
The other customers have no standing there, they have no relationship whatsoever that contract between the bank and another customer, they have no legal expectation to get the same conditions or to know what conditions other customers get. If the bank explicitly and intentionally lied that no other customers get so favorable conditions, that might be false advertising but I'm not sure, I'd expect a reasonable court to interpret that a bank "telling your customers you don't and can't do this" is exaggeration/puffery (i.e. permissible) and doesn't have to literally mean that they're not doing that for anyone, it means that they absolutely refuse to do it for you.
