That they choose to implement it by fingerprinting my access patterns without first disclosing is where they shit the bed. It isn't "sneaky" it's straight up sneaky (and dishonest and unscrupulous while we're at it). That this particular instance is harmless doesn't give me much comfort. Who's to say they aren't harvesting PII?
That their actions make sense for their business isn't any reason for people to accept their deceitful, customer-hostile decisions.
Or maybe you don't understand this hypothetical situation either, but I'm suspecting you just don't care about other people's privacy.