I put a ton of miles on them and think I keep them forever, but nothing like you do.
I like to buy 3 years old with as low mileage as I can find and then drive it into the dirt. My last Escalade was retired with 185k miles, but only after 5 years. I've put 75 on the new one after 3 years and it's bot 100k now so I'll probably have it another 2 or 3 years.
My wife just got rid of a 2011 450GL that she's had since 14 that's got 135k miles on it. I just don't think you get your money's worth unless you keep them 5 years or so.