There were some rides I paid $100 and was well worth it.
In Arizona, the Tour De Tucson was a blast. Support on almost every corner of the 106 mile ride. Streets lined with people but that was years ago. Compared to the big rides our here in California, no way are they worth $100. Solvang, Amtrak, all the big fun rides do not compare to Tucson as far as support thought I hear plenty of good reviews. Tuscons is by far the best. I even did a metric in Casa Grande Arizona that was pretty close to the same as far as support for a small ride.
The rides I do think were worth $100 in California are the big climbing rides like Breathless Agony and Ride Around the Bear (RAB no longer exists). But these rides were awesome timed events and one needs the support climbing 10,000-12,000 ft over 100 miles. Those I will happily pay and hopefully I will again.