I think it's extremely selfish to expect others to expend so much energy and time to carry your remains so far away, when you wouldn't know the difference.
I also think seeing night lights from a city on the moon would be pretty cool.
Approximately equivalent to a trans-pacific jet flight.
One way is in the fuel itself. For instance the Space Shuttle main engine was powered by combustion generated from liquid hydrogen + liquid oxygen - the exhaust was literally water vapor.
A second interesting nuance is that any fuel burnt outside of Earth's atmosphere is a carbon reduction, so a hypothetical rocket that could get out of the atmosphere on 50% of its fuel would be net neutral/negative.
Also wouldn't the carbon dioxide burned outside of the atmosphere eventually comes back down? The nozzle is usually pointed towards the Earth, so unless the exhaust is on an escape trajectory it wouldn't be lost.