It's still not ideal because there's more than just Co2 coming from exhaust, but even if that was solved, is there actually enough waste to meet current demand?

It's still not ideal because there's more than just Co2 coming from exhaust, but even if that was solved, is there actually enough waste to meet current demand? Some low effort googling shows there's over 100bn gallons of gas a year used in the US, 320 million tons of crop waste, and it takes 26lbs of corn to make 1 gallon of ethanol. Actually collecting and converting all the waste doesn't seem like an easy task or we'd presumably be doing it already, maybe it's cheaper to do EVs?