Yes, I did some stamp collecting and coin collecting too.
Two other hobbies which young people today just don’t seem to have much interest in.
I remember back in my day, you could still find Buffalo nickels and Mercury dimes in circulation, and you could find them in pocket change. It was possible to assemble a nice collection of the coins then. Not sure you could do the same today, in terms of collecting many years past of old coins today.
That's funny, I also collected stamps and coins as a kid. I had a 6th grade teacher who owned vending machines on the side. He had us help him go through the change from the vending machines to find buffalo nickles and mercury dimes (which, he kept for himself!). But that gave me the bug. As you suggest, he made a LOT of money collecting coins. He gave up teaching and opened a stamp/coin store and then two minature golf courses, one in Hawaii!
We stayed friends for almost ten years, well in to my teen years. He finally sold everything and moved to Hawaii. And to think, I helped sort the coins that made his move possible. Ha!!