At that point the company is subject to practically anonymous shareholders through many levels of abstraction. Voting is then done based purely on financials and often short term gains, which really puts a company at odds with their customers. So I have no customer loyalty to a company that's publicly traded.

Many private companies can still maintain my loyalty though based purely on their actions if the owner(s) / investors aren't completely disconnected from their customers. That's more of a case by case. The smaller they are, the more likely they care about their customers (there are always exceptions though).