I think many people will buy 'better' tools, equipment, and supplies equipment as their interest and knowledge in a particular area grows - carpenters, welders, sewers/quilters, cooks/chefs, other artists (in whatever medium they are using)
I think as one becomes more experienced, one becomes more aware what is 'appropriate' to use for particular projects.
I have learned that the 'biggest/'bes'/most expensive,most complicated' isn't always the most useful thing.
In some cases, I don't think there is a line that is crossed when a person becomes 'an artist' and stops being 'a hobbyist.'