>>1496559*avg* cyclist can pull 16 mph over reasonably flat ground while getting gross. This is being generous for a few reasons but w/e. An ebike can comfortably pull 20-27 for at least an hour of straight riding which is farther than most cyclists need to ride to get anywhere and you get there w/o being a sopping mess.
This alone makes cheap chinese ebikes better for most people than their city bike/ cruiser.
As for the fat tires, suspension is a pain in the ass to maintain and generally starts to lock up and be useless weight for standard riders after not too long. Fat tires provide reasonable suspension/vibration dampening and allow you to ditch the extra expense and maintenance of shocks.
Normally this is dumb on roads cause rolling resistance out the ass but the motor effectively negates this w/o much battery penalty.
Taken together, this makes chinese fat tire ebikes a pretty solid "it just werks" solution for people who would otherwise want to ride a cruiser or city bike around town. Coupled with them being pretty water resistant and the year-round ride-able conditions in Florida and I don't see why this is surprising at all.
t. bro who used to run an ebike shop