As far as having the plant on an 18/ schedule, like Jon said it really saves on electric, while only decreasing total yield by a small amount (theoretically)

Weed can photosynthesize 24 hrs a day technically, although this is not possible in nature, since the type of photosynthesis pathway it performs does not require a rest cycle for respiration (unlike pineapples for example which do).

Also the reason why you get shake for cheaper than buds is because the potency of buds is higher. I agree that it makes no sense to spend 4 times as much for nugs vs the shake from the same shit, just like to me it makes no sense to spend 4X as much on premium booze vs the cheap stuff.

Your plants look great by the way and I wouldn't top them more than once myself especially considering how bushy Blue Dream is as a sativa dom strain.