my experience is the wheel cost is not significant, when we in IT7 went to 15" Nittos from 13" Hoosiers the cost for 4 wheels and tires was about the same price as a set of Hoosiers.
the way we structured the rules in New England is you can run any tire but you only get year end points on Nittos. That way the new guys can race with the shit they have laying around.

even with my positive experience the main reason i support this is having some differentiation between class. there is so little difference between T, ST, Limited Prep Prod and IT that it just makes sense to me to have classes that offer a different experience.