This is an interesting point actually.
I think you can tell a lot about the personality of the seller buy their choice of sourcing methods. When I started, I was out and about doing garage sales, auctions, weekend markets and charity stores searching for stock and that's where I got my pleasure from. It didn't come from the actual sales, it came from the hunt itself.
The more I hunted, the more I found, the more I sold, so the hunting itself was where I got the drive from through the enjoyment of it and the reward came from the growing sales. So they both feed into each other.
So I think there are definitely hunters, those like me that love the product hunt itself. We're a completely different animal to those that wholesale or dropship I think. I know that would bore me stupid, no thrill of the actual hunt to enjoy. Where as others would think sellers like me are crazy for getting up at insane hours, travelling for ages and then spending all day sticking our noses through other people's belongings trying to make money, when you could stay in bed and then sit at the PC and list products without even leaving the house lol.
Same as anything I guess, we all look to get different things out of life. No different to sales, some treat it as an adventure, so just want to make spending money for the weekend and so on.