1. But it is
simple morphological fact that leaves produce photosynthate and flowers produce seed.
Saying flowers produce any sizable amount of energy is like saying we piss through our skin when we sweat. Yeah, it's basically true, but you're reeeeeeaaally stretching it there.
2. Green fruits produce some energy too, but you wont see a producer of grapes, apple, etc plucking leaves so the fruit can get light (at least for any other purpose than to make the fruits look more colorful, but even then they don't do it).
3. Vince, I will give you this: veg time does build up starches in the woody areas of the plant, and the plant can convert these back into usable sugars when it needs to: when animals or people or wind pluck the leaves off of the plant.
4. Now you can argue that the way we cultivate weed is more or less for one great push to bust out big flowers, and so it doesn't matter how you do it, if its good or bad for the plant... The results are your reasoning. But the physiological truth is this: you are forcing a plant to tap into secondary metabolic pathways. These are not things a plant likes doing. They are much less efficient, and therefore undesirable. Any other production seeks to keep stressors from occurring, they certainly don't promote their occurrence.
Done. Lol. And with a smile!