Wut?

No, like seriously, really?

"Which is stupid, cuz theres no such thing as automobile fuel residue when you drive"

Yes, there is; it's called exhaust. You know that pipe that gets really hot and makes noise and on cold mornings produces a little bit of fog? Ever notice how water drips out of it sometimes?

Gasoline is a hydrocarbon, specifically C8H18. The combustion process that makes engines work is 2 C8H18 + 25 O2 → 16 CO2 + 18 H2O. If you notice the last part which is 18 H2O, that's water. Now when you heat water up extremely hot you get steam, and when you cool it extremely quickly you get clouds; exactly like on that cold day when you exhale and can see your breath, that is water vapor in your breath turning into a tiny cloud. That's exactly what is happening with airplanes only at a much larger scale. Instead of the milliliters of water in your breath it is gallons of water in the plane exhaust; and it's very cold a couple miles up into the air, so magically it turns into clouds just like your breath does.

Even if they were putting stuff into the air, the amount needed after it disperses over the entire planet would weigh more than the plane itself and never make it into the air. It would be extremely inefficient to poison you with something when they could just put it in the tap water instead.