You are exactly right. I have always been fascinated by electric powered vehicles. As an experiment I built up two bicycles, one with an electric hub motor and the other with a 2 stroke Chinese gasoline engine. Both the gas engine and the electric hub motor came as kits from eBay.
The gas engine came with everything for $80 including shipping. I put it on an old mountain bike and it was quite impressive. The bike with the engine and full fuel weighed about 70 pounds. The tank held about a gallon but it would take you a long ways. It would do 35mph and had a completely different feel than a motorcycle or mini-bike. Despite having only a clutch and no transmission it had impressive power in its “power band”. It was of course noisy, smoky, and not street legal.
The “brushless” electric motor kit cost more than $200 and I had to buy the batteries locally for $130 along with a case and rack to hold them for another $50. I put them on a “hybrid” bicycle I got from Walmart. The complete package with the bicycle weighed over 100 pounds, but compared to electric bikes available commercially I had twice the power and twice the range. It would go 25mph on the flat and had a range of 25 miles. Technically it was not street legal, because it went faster on its own than what is allowed, but from a practical standpoint I doubt whether you would ever get a ticket.
Compared to the gas engine powered bike it had 1/4 the range, 1/4 the power and weighed approximately 50% more. It didn't climb steep hills well. Once you ran the batteries down the electric scooter charger I had took basically all night to charge them back up. The advantages were that it was basically silent, you could ride past the police without getting in trouble, you didn't have to start the engine, and it didn't make any smoke.
I feel that fooling around with the two bicycles did give me a better understanding of how electric vehicles compare to gasoline powered vehicles. I think that it would be a good “science fair” project for kids, although I am not sure that it would result in politically correct conclusions.