Even the usual car parts stores (Autozone, Advance auto, etc.) stock a lot of parts going back at least 30 years. My car is over 20 years old and I'm surprised

Even the usual car parts stores (Autozone, Advance auto, etc.) stock a lot of parts going back at least 30 years. My car is over 20 years old and I'm surprised how many basic parts I've been able to just walk into a store and buy (radiator, alternator, starter, etc). The amount of warehouse space in those stores does not seem that big but they manage to keep a very useful selection of parts spanning several decades. Much more convenient than going to a dealership and paying 3x the price and waiting a week because they don't actually stock the parts anyway.