Knitting can be quite fun and somewhat low cost if you don't get influenced too much. But ask any knitter about their stash and you'll discover we're all hoarders who will not hesitate to pay ridiculous amounts of money for a single skein of hand died yarn (in the ugliest colours) that most likely will end up in the stash and never get knitted. Tools are the same. Why settle for a very basic and fully functional set of needles when you can get the most expensive one?
If you know a knitter, just know they are most likely sitting on a small fortune worth of yarn and tools.