I have never tried road racing, though I have wanted to, so my response is that of somebody who’s considered it, but never bitten the bullet.
My first complaint is the money, yes. My local road racing series is NCK in Northern California. Looking at the entry fees for the race at the end of the month at it is $200 for 1 class, 1 day, so $400 if I wanted to race both days. Those prices are for non-member. Annual membership is $130, or $20 for a one event membership. At my local sprint track, I pay $300 for an annual membership, can practice whenever I want, and pay barely $300 in registration for the course of the whole season! So, even if I just wanted to give road racing a try, I’d nearly double my entry budget for one weekend!
Second, at this kind of ties into money, I have a KT100 and 206 is very popular in my area. To me, and maybe the fact I’ve never tried it would prove this very wrong, but to me, I would not expect these types of classes would to be that much fun because my perception is you would be full throttle for almost the whole lap. Yes, taking corners at high speeds could be more challenging than a sprint track, but at the same time, one of my least favorite sprint tracks in my area is mostly flat out and it gets pretty monotonous. So, to make road racing more challenging and fun, I’d think you’d need at least a 125 shifter, but those are much more expensive.
Which takes me finally to new people. New people shouldn’t be hopping in a 125 shifter on a road course, but that’s where the entries are. For my Yamaha, I’d only have one other person to race. That’s not very attractive.