Timing stops for megachargers will be a whole lot more difficult than truck stops until they are as ubiquitous. If you have to use a plain old supercharger your talking 8-10 hours for a charge, don't even bother with a normal plug of any kind.
A charging station with 10 megachargers going at the same time will draw as much power as a small city of say 10,000 homes.
I'm not sure what you mean here. In the US, scales are used to ensure compliance with axle load limits, not to determine any costs.
In any case, since they don't need the weight of a diesel engine, transmission, fuel tanks, or emissions systems I'm not sure how the weight balance will work out.
Then people with ~500 mile routes that can charge at both ends. grow from there.
Does the Semi have a sleeper cab? If not, it won't be used on long-haul routes regardless of battery.