I'm sure once you add up all the costs, the scooters will still be cheaper, but the is a lot more to cost per mile than gasoline
I'm retired now, so I don't keep track like when I did for business miles, cheaper/mile than any motorcycle I have ever owned, was an '82 BMW 320i. why, I didn't have to spend $350 every 5000 miles for tires, + chains & sprockets, more frequent maintenance schedule, I could go on, one year my SV650, I spent $2500 just in tires, my little bimmer took cheap 13" tires that lasted 80,000 miles
My V-strom 1000, you don't even want to know, and yes, my Silverado is cheaper.