All this talk about "commitments" sounds an awful lot like "the social contract" to me. I challenge each of you to define these "commitments" you speak of in objective terms.
If a child registers for TBall and their parent pays the fee, what is the nature of the "commitment" they have made? Has a contract been established? between the parent/child? or child/teammates?
sensedata, if " once [you] had started a season and [your parents] had paid money on [your] behalf for [you]
to play then [you] had to honor that commitment and finish the season out
or find a way to pay them back." were you obligated to pay back the entire amount? or a prorated amount? What if you continued to show up, but picked dandelions in the outfield the whole game? Where these terms explained to you before signing up, or did your parents just make them up arbitrarily? Is the registration fee paid a gift from parent to child? or a payment for future performance?
Here's what my wife and I came up with: quitting is not a moral dilemma, but rather a calculation of costs versus benefits; we plan to pay for our children's activities without strings attached, they will be gifts. That being said, if gifts are squandered that cannot help but influence the future flow of gifts. We will encourage our children to try new things, but if they feel like they want to quit, we will sit down with them and try to flesh out all the possible costs/benefits. I find that before I began to explore myself and others, I actively avoided knowledge of costs/benefits which might contradict my emotional response. Costs of quitting might include loss of opportunity for unexpected enjoyment, disappointment of teammates, social ostracism, but I will contend that loss of the entry fee is not a factor in the decision, as it is a sunk cost. Benefits however, might include free time generated by quitting, an opportunity for the bench warmer to play, a sense that your parents respect your decisions.
"Should a Dr doing life saving surgery just quit if he feels like it?"
Absolutely! The doctor performs a surgery, he is paid a fee, all accounts are settled, that's how a free market works. You don't have to respect his decision, but if a doctor is evil because he stops performing crucial surgeries, what if he goes on vacation? What if he wants to watch his son's baseball game? Does his ability constitute a moral obligation? What if he wants to be a painter instead?
PS: I hate the term "life saving" no lives can ever be 'saved' (the mortality rate for humans is 100%), a doctor can only increase ones odd of living another day. Also, it's the sickness which kills a patient, not the doctor who chooses not to operate on them.