So you're going to tell me you've never seen anyone ride their cart?
I'm not going to say "
never" ... but it's incredibly rare to see someone ride their cart at the stores around me. Mileage obviously varies.
Local topography might be a factor. Every single parking lot around here, without exception, is pancake flat. I guess you could ride your cart from the store to your car ... but you'd be doing a heckuva lot of work to keep it moving. There's no riding the cart downhill around here. It would be like riding a heavy, awkward skateboard.