I did it willingly because I wanted money. I did not have to. I was able to afford a lot of things back then and paid for things I needed. I learned a lot of things too. If you have had a negative experience you cannot say that all will have the same. That prejudges the outcome based on a theory they will all be negative.
If you where working so you could afford things you NEEDED, you where not working willingly. Needs are normally provided by parents. If they are not providing them, then you had no choice but to work to obtain them yourself. It wasn't a choice. Or are you confusing needs with wants and desires which your parents wouldn't buy, because they wanted to teach you how to earn/save buy.. aka responsibility? We aren't talking about baby sitting, or meowing people's lawns, stuff that kids do today as well, just like when you where 12 years old. Because their parents won't buy them something and expect them to earn and save for it, teaching them a life lesson about money and responsibility. We are talking about working, getting a pay check, paying taxes and actually providing actual needs.
Did you have to buy all of your own clothes, shoes, etc? Did you have provide and pay for your own lunches at school (sorry, no free lunch here), bed/dresser/room furniture, and everything else short of the roof over your head and 1 meal a day? Did you work a full time job (40 hours + a week by the age 15) along with milking goats, cutting firewood, doing all other regular house hold chores, and going to school full time? I also wasn't allowed to get rides home, I was required to ride my bike 5 miles home... Yes my dad was a hard ass prick. (Obviously I didn't work a full time job at the age of 8, but I did work about 15 hours a week).
The answer to all of that is NO! As you already stated you didn't have to work, which means either your parents would have bought you ever want you desired. OR, you are manipulating the truth, where it was because your parents wouldn't buy those things, and you had to earn it because your parents where teaching you responsibility. I suspect your "I didn't have to" was you had to, if you wanted something special, because your parents wouldn't pay for it. Which is no different than what takes place today with most kids and parents, working to earn want's because their parents are teaching them responsibility.
All you sound like is a privileged "rich kid", who didn't understand the lesson their parents where teaching them thinking you had a choice, and who doesn't understand the difference between working for actual life necessity needs vs working for wants and desires.. Specially when you where a 12 year old being taught responsibility by your parents.