Not syaying that $40 is right or wrong, but you should take a minute to think through the numbers to see if it is justified. If you work the numbers backwards, a $40 retail price item cost the hobby shop anywhere from $25 to $30 from the distributor plus shipping. The distributor needs to make a profit and will pay anywhere from $18 to $20. The manufacturer has the shipping costs to the distributor, packaging, raw materials, over head, advertising, insurance, and all the free stuff they give to sponsored drivers to cover. If they are going to make any money they need to be able to make the $40 retail item for about $8. That includes the molds which can costs thousands of dollars per wheel/tire.
So, for a company to come along with a $20 set, they would have to make them for a whopping $4 a set. Hmmmmmmmmmm....$40 does not sound too bad to me for what you get. And everyone wonders why the little guys can't survive in the industry?