My daughter works while being in college and even pays most of her own rent.
Funny enough, to teach her the value of money we did sent her to Europe but backpacking and doing workaway programs (work for a place to sleep and some places would actually fed her), cost us little and at 18 she learned pretty fast what it takes to be on your own and on top of that she got to see other cultures and had a blast.
We did send her some money for food every now and then but not much, but she would go to the markets and got the produce at a discount towards the end of the day, even the menu of the day in most places was in her mind too much to spend, so she usually cooked her own food and found the best bargains, specially on fruits and vegetables that have been sitting for half a day and discounted towards the end of the day.
Now she is very frugal and doesn't like to waste food. She was going to college to be on her own anyways and I did some traveling at her age myself (then again I was still in Spain so it was easy for me).
Some of our friends couldn't understand why on earth would we send her to foreign countries on her own, on how dangerous that is, etc etc etc. Being on your own is really not that dangerous, I find the US more dangerous than Europe, and at 18 is about the best age to see the world on your own (six months).
One funny thing is that one day she was on Italy called us to ask us for permission to go to Berlin with some friends (she made a lot of friends over her trip) me and my wife looked at each other a bit perplexed and replied to her, "Don't you get it? you are an adult now, but thanks for asking, just keep us informed on your whereabouts and phone numbers of your friends in case we don't hear from you".
Many here might not agree on what we did, but that's our version of kicking our kids out of the nest because it's time to learn to fly.
And I know what that trip meant to her because I did the same, my wife did the same at her age as well. You just can't do that on your mid 20s or older because no one is going to let you stay at their place. At the end of your teens you find open doors everywhere.
Of course when she came back she was a bit condescending towards everyone because she was a world traveler and she knew everything worth to know in this earth because of her six month adventure. But that was two years and a half ago when she came back to go to college, and she has been pretty independent ever since.
Another funny thing is that her grand parents from my wife side, have never been outside of the US. So we are taking them along to visit my parents in Spain in September, they've never met in person and I'm past half a century old so it's about time they meet before they can't, and it's been a long time since I saw my parents last. My daughter has seen them more than me on the last decade.