How do you make kids earn things?

This little boy is upset because he got his toy taken away for being bad. He kept asking and I said NO. He can pout all he wants but he ain't getting it until he earns it. He was being nasty to his friends. I think some people these days are being too soft on their kids and it's said that some adult are giving in to temper tantrums. I don't put up with them. Kids need tough love.
I work at a preschool. Some teacher thought I was being too tough but I don't care. I'm doing my job. I don't care about being liked or disliked.