This would actually be a good business opportunity: hire such "grade 8 educated" people as office managers, but pay them much less than MBAs. If they are nearly as good as MBAs, you save a lot of money on this group of employees, and thus your company has a strong economic advantage.
The trouble is it's performance all the way up and down. In the first place you're only going to get the weirdos / extreme gamblers, and then you'll struggle to attract investors, your clients/suppliers will wonder why your business development folks missed their classical references...
You will (hopefully) nevertheless check whether an applicant has the necessary traits to be a decent office manager. On the other hand, I wouldn't claim that weirdos are necessarily bad office managers.
For higher education there is charade of education to get jobs. So for office manager job where grade 8 would be enough, we have MBAs now because we all need advanced education to survive in global economy blah..blah.