Why do my parents get mad at me for spending my own money?

Carpentry is one of my hobbies and I tend to buy tools a lot and they get mad at me when I buy a new tool. I actually haven't had much time to actually build anything lately but I continue to buy new tools, which is kind of a hobby of mine also. They get mad when the ups man shows up at the door. Honestly I haven't really bought any tools lately because they got too mad a me. It's upsetting to me because everyone has something that they look forward to in life that gives them a reason to get out of bed each morning and this is one of those things that makes me happy. I don't understand why they get so mad at me if it's my money that I spend. Any thoughts? I get tired of trying to avoid stepping on everyones toes all the time. It's stressful for me cause I never know when I'll get yelled at next for something. This isn't the only thing they try to control but I can't really think of anything else at the moment.
Updates
+1 y
I don't live at home and I pay for everything.
Why do my parents get mad at me for spending my own money?
Post Opinion