If they had, we'd have run out much sooner and would now be back to the horse and buggy.9?Luddite)
Good thing someone didn't invent the internal combustion engine in the 1700's, oil (and gasoline) was really scarce then!lol! And a good point. As if scarcity was a problem in 1900 when there was hardly any use of gasoline. I guess that's part of the allure of hydrogen or bio-diesel, that the sources are everywhere.
As for horses, they certainly were a major source of urban pollution and disease. On top of cruel treatment, the other problem with horses was space for housing them and their hay. The automobile beautifully answered these problems, especially since gasoline was easier to store than hay and, ironically, a lesser source of fires, and because cars could be stacked on top of each other in that marvelous invention, the mult-floor garage. Additionally, cars moved faster and were shorter than horse & carriage, which meant more and better flowing street traffic. The automobile truly opened up cities for better use of space.