Some of those Canadian people probably did not have a good business plan, but it is clear the British government doesn't like the idea of a small grower with a few plants. Even though that should be allowed as much as it is with brewing.
There were Conservative politicians who got up and publicly said that toddlers would die cause they'd eat marijuana plants grown by their parents!
I wouldn't blame the business plans so much. A lot of them applied for licenses but didn't get theirs approved till after the huge players did. By then, the market had already consolidated.