Laser weeds have been shown to have important protective effects on the soil and to assist with bee naviagation.

From what I've been hearing is its all marketing and no farmers are actually using it. Basically it is financially nonsensical compared to chemical herbicides. That and driving a tractor through the fields 2, 3 or 4 more times at 2-3 MPH per season isn't great. Basically more of a solution looking for a problem.