If you are getting more productivity out of people by adding significant constraints to their schedule such as where and when they work I think it's most likely that you're measuring productivity wrong. It just doesn't make sense purely from a logistics standpoint.
I understand that remote work is going to be abused by some people. But you probably don't want those people in an office either. You don't want them at all.
The benefits of remote work for both the employer and employee leaves me with no doubt that it will continue to gain ground.