I don't blame you for being unhappy about this. So, basically what he told you was that he charged you to give him new ideas for cue designs that he could use for sale to the public, and he would have charged you more for it to be exclusive.
No, that's just wrong. Your design belongs to you. First, he needs your permission to use it for public sale, and second it's totally justified for you to receive a fee from him for reuse of your design, not the other way around.
Fran, as I tried to explained in my last post, it's not that uncommon for a maker to reuse a customers design that THEY built a cue for, especially for low to mid priced custom cues. A maker will normally not charge a program or template fee as long as the design is not a 1 of 1. Time is $. Makers without CNC technology have to order special templates just for one design and those can cost hundreds EACH. Makers with CNC technology have to "fit" the design to the cue to the customers liking and then program the code used in the construction of the cue. Cost can be more reasonable if the customer chooses between a set of designs already in stock from that maker and in most cases that's the way most will go. If the customer say's they want it to be 1 of 1 THEN the customer may be charged design AND programming or template fees which can be very substantial depending on the design. The OP didn't specify that his design could not be used and if he did the maker would have adjusted the price accordingly for his custom time. Now there is a chance if the maker wants the business he may agree to a 1 of 1 and not upcharge but that is something has has to be asked at the time of order...
IMO. It was the fault of the OP NOT the maker in this case