I just don't see the purpose this serves in promoting better education. Saying places do it doesn't make it a reasonable model of education and I don't see an actual rationale for it that benefits the student. If the school is a for profit, it makes sense. If the school is a not for profit/state school, then the purpose is for the service provided and then I have to ask what potential reason a school would have for doing this:
1. Are the schools concerned that they will be unable to keep students who commit and attend their school to train?
Is the fee really the biggest issue if a school can't get people to commit to their program? Probably not. As folks have advised and discussed here, a few hundred bucks is easy to give up if necessary so that doesn't 'lock' anyone in to attending a school. It just takes money from the prospective student if they back out. So the issue is 'why would they back out to start with' and that's a question about the educational system/support provided within the program.
2. Are the schools concerned that they will not be able to remain solvent without the additional funds?
Having a fee doesn't seem to be the issue here since its refundable (so long as you stay in), so it can't be to stay solvent. And even if it was, that is not a justification for an educational system. Thats a buisness model and we've seen how well those work for promoting psychology training.
3. Are the schools so full of extra money that they want to make sure a student comes or they'll lose it based on a yearly budget?
If this were the case it doesn't seem like a fee would be needed. Better funded places are more popular and, by nature, are more likely to retain commitments.
I just don't see any rationale actually sticking around and making sense as a necessary and beneficial requirement. Thats why I think its a gimmick.