By someone who sees service in a very positive light:
It is a matter of choice. You choose to serve others, to see it as a divine gift and to be filled with joy, awe and magic. You could also see it as a simple unpaid chore and feel miserable and make everyone miserable. The act is the same; the attitude is different and so the atmosphere you create is different.
Here's the big idea: If children are allowed to turn foods down, they're not forced to eat, and they're given choices, they will come to choose good foods, know when they're hungry and when they're not, and actually learn to listen to their bodies and know what they need.