- It's much easier to grow plants inside because you don't have to worry about weird weather like frost or insects or fungus etc.
- You can claim organic status and that puts you in a higher price bracket
- You don't need to spend anywhere near as much on transportation so that saves you lots of cash
- You can have much tighter control of supply/demand dynamics (for instance ship smaller batches) because of local proximity
I'm sure there are more but those are the ones that spring to mind.