That's how it should be, however, it happens the other way around too:

* Company's person in contact with the customer insults the customer/make fun of him/etc (or even swear)

* customer responds politely that it's wrong and uncalled for

* Company respond another sarcastic comment or that it's "not insults" (even when its crystal clear) and that you're in that class of annoying customers

* customer gets real angry

bonus points: * company goes personally against the customer and tries to threaten him by all possible means

Sounds like a true story? Well yeah, it is. ;-)