I might add, that before cars and trucks were invented. People use a lot of horses, to ride and pull cargo. And that resulted in quite a lot of methane, and horse poop to end up in city streets.
Big cities, like New York and Chicago, use to smell from all the horse manure. Automotive engines eliminated that health hazard, and the flies that loved it.
I guess we need city horse poop to return, so we can eat the bugs, they attract, as a protein source.