Yes, they'd move hundreds, if not a full thousand ruggedized MacBooks every year.The problem with 'in the field' computing is that you have money people making the decisions rather than practical people making the decisions. I work in the electronics repair industry and I have seen thousands of Apple ipads get damaged by 'in the field' workers because the ipad can just not handle the vigour's of 'in the field' use. I've seen Panasonic toughbooks take some real beatings, caught in a torrential downpour of rain, covered in mud, oil, food liquids (from manufacturing plants), run over by cars and they still go on working 100%. Drop an ipad on the company concrete floor and BAM, screen is broken, frame is dented and depending where the damage is, the home button not work, or the power button or the volume buttons.
Panasonic make some excellent toughbook tablets. There is 100% a market out there for mac os ruggedized laptops. If Apple was prepared to make a VR headset knowing it's take up would be low, they can surely make a ruggedized laptop which in my opinion would sell more numbers than the VR headset but oh look, Apple made a VR headset that has not sold as well as they expected and yet they are going to make other versions. A ruggedized macbook would sell much much better in my opinion.
This is why Tim Cook is not the man for Apple any more because he does not have the vison on where to take Apple products like Steve Jobs did.
If you're so convinced someone could make a killing on these, by all means get some talent and some investors together and find out yourself.