Surely if you drive around in them you have to pay huge insurance bills each year. Don't those bills add up to a super car's value after 30 years? An 18 year old would be charged as much as a lambo cost to insure it. A thirty year old would pay much less, but still a considerable sum each year, and that's only if he'd never made a claim.
You'd be surprised. Especially when you're into your 30s and beyond. A piece of shit 20 year old Citroen only cost $150 less than a V12 Aston Martin worth 100 times more when I was checking out insurance quotes. No idea why.
If you'd bought one of the current hot sellers in the last 2-3 years you'd no doubt make bank. There've been some insane price rises. If you'd cherished your whatever from new it probably absorbed its purchase price and more in keeping it rolling over the years.
I remember the car bubble of the late 80s. Investment banks were buying cars to stick in vaults believing they were on to a dead cert. Then it turned to dust in a truly stunning fashion. I bought an Alfa SZ around 2000 for about $18,000. In 1989-90 they were being advertised for $180,000 and more. Not such a hot investment after all.