But then the issue would be converting the overcompensating suburban lawn care company owner to switch to electric

I'm surprised they don't decline on the basis of battery charging. The batteries work for individual home owners, you can usually do your single-occupancy-home yard and charge the battery for next month or w/e, but these companies do apartments, businesses, highways, they might being doing yards that can't be done by one person, or on one battery, or they might be doing 12 yards in one day.

I don't know the logistics of switching from "fill up this portable gas tank at the start of the shift" to juggling batteries and charging from the back of a truck, you'll probably need to be able talk numbers to them that debunk the presumptions they will have about the upfront costs of switching hardware (progressively or all at once) and waiting around (unpaid standing around) for batteries to charge.