Ah, loyal customer is a commonly used term for a customer who has conducted business with a company for a long time. Not sure why you put it in quotes or why it confused you, but you can google it.
Yeah, OK. It's just that the outrage of TFA relies on the assumption that customers' loyalty implies companies' loyalty to them. It's arguably a foolish assumption. Especially about insurance companies, whose profitability relies on denying claims.
Not the assumption, the expectation. That's how capitalism is supposed to work, hence the outrage. "Caveat Emptor" shouldn't be a general business model.