No, I wouldn't do that. I'm actually having the opposite problem - trying to convince them that outfield is important. Since they get so little action out there they think its like being banished to Siberia despite what I tell them. In our league, a coach is able to be in the outfield to help give some direction so I spend a lot of time chatting them up to try to keep their heads in the game. Its actually been pretty helpful because I can explain some live game situations to them after the play to help them understand what happened or should have happened.
That was actually a bit of a joke, Mosh. Another active thread is about a rec coach who was forced out for, among other things, using outfield as punishment. ... But it is good advice.
My best tip is to teach the proper throwing mechanics. Looking back, that's the thing I regret not focusing more on. That stuff is hard to fix later.
The other thing is to teach them is that softball is fun. If they think it's fun, they'll keep playing. The best players in 4 years won't be will be the ones who are the most advanced now. It will be the ones who kept playing because their coaches kept it fun.