The problem is right there in front of the eyes! They look like regular scooters so people assume they're regular scooters capable of navigating in traffic at higher speeds than most pedal vehicles. Car/truck drivers will mistake their maneuvering capabilities while people on walkway/bikepath may panic seeing what looks like a MOTOR VEHICLE on the path and do something like jump out of the way, take evasive actions and/or possibly hurt themselves in the process.
If you take the motor off and it can no longer be used - it needs to be treated as a motor vehicle.