As many of you know, I am one of those fruit/veg market farmers.
As has already been noted, most of North American farmers have to deal with specific growing seasons, unless they have greenhouses (and those are hugely expensive to operate).
During the season, I grow for local market sales and, if I happen to have excess product, to the local grocery in town. I also do a great deal of canning, freezing and other food preservation to tide us over until the next growing season harvests.

I refuse to do business with wholesalers and canners. They have proven over and over to be slimy operators (the horror stories I could tell you are Trump business level shenanigans).

I do have a greenhouse and cold frames, but they are only for personal use for family and close friends during the off-growing season.

Also, I’m here to tell you that a greenhouse tomato will NEVER begin to compare with a field/garden grown summer tomato. FACT.