A snail crawls about 2.5 meters an hour.[From Facts]
But still, FedEx's snail delivery service - FedEx Ground - takes 8 days to deliver a package from Oregon to me, a fact I learned to my horror just this morning, when I was notified a USB hub I ordered from LaCie (in Oregon) would not arrive here until Friday next. Nonetheless, the delivery charge on the hub is less than it would cost me for gas if I drove to the nearest store that stocks the hub. So I guess it's worth the wait.
I suppose, too, that's as good an example as any of the savings to be found in mass transportation. If you can ship a product clear across the country for the average cost of 1.5 gallons of gas, that sounds like a pretty good deal to me.