Ok, and why that? I.e. you are explaining the answer with the question. In particular, I want to understand the motivation why people buy into that.
There's only one motivation for hobbies: People like it. Why do they like it? Because they just do. It's the emotional part of being human. There's no sense in asking why, it just is.
Why do I like peanut butter? Because it tastes good? Well, yes, but why do I think it tastes good? I don't know!
Same with old cars. Someone buys a bucket of rust for 3000 bucks, and then starts fixing it up, spending another 3000 bucks in the process and a lot of time. Why? Because they enjoy doing that. Why do they enjoy doing that? They just do.
Don't try to explain or understand the emotional part of being human, there's just no point.