The company has been has been squeezing their franchisees out and buying them up along with buying back their stock for a long time now, decades in fact, so tier stock is naturally higher than it would be on the market. They dump it and it drops back down.
All stocks are grossly over-valued currently, and have been for a while. Many are losing value now that the govt. raised interest rates and free money for big borrowers is going away. 70% of the domestic economy relies on consumer debt rising, and that isn't happening, so look for a recession soon, if not a depression, since wages and disposable income have fallen even more the last year. Wealth is concentrated at the top and it has run out of places to stash it, hence hyper-inflated stock prices.