The short answer: No. A hobby, no matter how passionate you are about it, does not create these sort of traits.
I think a better question might be, "What type of person embraces the UL philosophy?" Previous threads have suggested a strong association between personality type (INTJ) and UL backpacking, as well as an over-representation of certain careers (eg. engineer). I think the hobby provides the outlet to express traits that are already there. And if you weren't spending the money on gear, maybe it would be car or bike parts, cookware, antiques, or whatever else you were into.
I'm personally introverted, performance-oriented, and minimalistic, so UL backpacking and fastpacking are great matches for me. And while, like most here, I have situation specific gear (at least a 3 season set and a winter set with some crossover), I use everything I own pretty frequently. If I don't, it gets sold or donated. The questions we all ask, "Do I really need it", "Could I use something multipurpose instead", "Is this the lightest of its kind" before each trip, now get asked of all my possessions and before any purchase, so net possessions have been steadily going down over time.
It is pretty clear from the variety of postings that everyone has a slightly different perception of UL backpacking, but these differences mostly stem from what each individual brings to the table.
edit- I really like Dale's theory on hypermaterialism. Owning a few select really, really good items, selected for specific criteria and used frequently, vs a whole closet of crap used once in a while.