Is rudeness and arrogance the price of an advert?

Customer care and just general politeness seems to have taken a holiday. Issues that are very minor, in the greater scheme of things seem to take on huge importance, out of all proportion to their relative importance. Is it that people are under huge pressure, because we are all in the same boat?
Why is it that grovelling seems to be the only way they want to relate to sales people. Instead of saying we have a transaction between equals and you pay for a certain size advert and receive your value and good service without getting to treat the sales person like dirt.
Sentences that start with " we spend so much with you" usually come from clients that are spending very little in the first place, but seem to want blood with their pound of flesh. Is this psychological terror acceptable or should some clients be shown the door?

Note: this forum has been moderated.