I agree with you in your concern about giving an undesererving business your patronage.
Money is sometimes (unfortunately) the only way we can make a statement. Whether it is a vote of confidence in a quality product/business, or disapproval for disrespectful (& very tacky) business behaviour, such as what you experienced.
As long as people "don't care" how they're treated by this individuals like this or not, he/they will continue to do this to others. Being that we have a choice in the matter, why perpetuate such practices by supporting those behind them? That is, afterall, in essence, what we do when we close our eyes to such things.
I would search deeper for a viable, comparably effective alternative, provided by a more suitable company that will value YOU as YOU deserve. We are challenged enough in daily life for free, so why PAY money out of your pocket to be insulted by someone who can't appreciate the hand that feeds him???
That, of course, is my humble opinion.
"The measure of a true gentelman is the respect with which he treats all individuals, ESPECIALLY those who are of no value to him". -Author unknown