Comes down to you can't expect anything without first putting in some effort. My oldest Daughter just finished vacuuming the house so she can play xbox. She did what she was told to do and then turned around and did an extra room just because. She didn't even point it out to me, just did the work.

Tonight after dinner, which she is going to help cook (new cooking with kids post coming), I'll take everyone out for frozen yogurt as thank you for her added effort.

Little rewards for little efforts help a child learn things aren't free in life.