Market processes "give", and for that we should be grateful, but they can also "take away", which is why many look to law and collective bargaining to secure their past gains. Those people are wrong about a lot of things. They may be in for a rude awakening if productivity declines as benefits rise, but it's not as though they are behaving irrationally or immorally.
Not likely. Ask any employer who has had to deal with teenagers. Most don't want to work and we don't want to hire them. The age range for productive employment has moved up beyond the child labor restrictions.
The child labor sweatshops in textiles and other dangerous industries are gone. Now those jobs are being done in other places by children of another color. They cannot return. The new sweatshops are burger joints and retail stores; places that give a kid a chance to build job skills and a work ethic.
Look at the nature of the child labor violations being prosecuted. Wal-Mart: because they work a kid 26 instead of 20 hours or because they kept someone until 11:00 pm instead letting them off at 9:00 pm. Six hours of work or two hours out of the day is a pretty marginal gain for society for interfering with a willing employer and a willing employee. Maybe we need more midnight basketball instead of midnight shifts but I don't think so.
And what is the cost of this marginal gain? A generation of kids who have never done anything difficult. A generation who can't mow lawns, drive a tractor or stock shelves. It may be the natural evolution into a higher plane of social development but kids are becoming fundimentally, definitionally, different from previous generations. I keep looking for the positive aspects of this but I just can't see them. These kids are weaker, less mature, less responsible and less capable. Society at large is less free and less dynamic than it could be.