Neil Young bought a portion of Lionel Trains back in 1992. He is listed as a co-inventor on seven Patents assigned to the company. Yes, that Neil Young.
If you make a lot of money, you have to spend it. And one way is to get into the hobby of model trains. And if that doesn't spend the money fast enough, you can buy the company, I suppose.
And if it really is your passion, you can invent new accessories for the trains and create new products for the company you just bought. And Neil Young has done just that. Yea, the guy with the guitar.
Unfortunately for Young, the company, Lionel LLC, ended up in Bankruptcy, after a couple of legal battles with competitors, and due to the decline in interest in model trains among the young (I had a Lionel 027 Santa Fe "Vista Dome" set, circa 1969, after the company had switched to cheaper plastic parts). Hobbyists seem to gravitate to HO and smaller scale sets, over time, as these took up less space than the massive O-gauge Lionel sets.
Today, Young is still a consultant to the company, but it is not clear whether he owns an interest in it.
Everyone has to have a hobby, I guess!