I'd assume they are just fake, take your money and use a different model under the hood. Because they already existed before the public release. I doubt that their backend rolled the dice on LMArena until nano-banana popped up. And that was the only way to use it until today.

Agreed, I didn't mean to imply that they were even attempting to run the actual nano banana, even through LMarena.

There is a whole spectrum of potential sketchiness to explore with these, since I see a few "sign in with Google" buttons that remind me of phishing landing pages.