Sometimes I write angrily to companies. Usually not on the first email (though it can be incredibly formal).

The cases I can remember is bike rental company that didn't want to provide a receipt, airline that didn't want to accept a complaint (by making impossible to understand complaint flows), company that didn't stop stop marketing email after several reports.

So many companies are treating their customers incredibly badly.

This becomes a tax on the companies that does not treat their customers badly.

Bad customer behavior is a cost of doing business - and I honestly understand why customers are coming out hard.