Before you tell me how much energy the Earth gets compared to how much we use, I'm going to pre-emptively reply "Exponential growth".
Not much more than you are otherwise loosing by using the oil instead of burning it. The hard part is getting carbon - not a lot of CO2 in the air.
> I'm going to pre-emptively reply "Exponential growth".
But we are not having exponential population growth right now. And even if we were, the universe is big REALLY big, stupendously unimaginably big. Even just the Earth is enormous, and we are nowhere close to filling it up.
And to bring things back to this earth, this isn't going to be a problem for such a long time that predicting anything whatsoever about it is futile.
This seems to discount tidal, wind, and geothermal energy sources. Wearable devices that capture kinetic movements are a possibility too. As technology progresses, efficiency increases.
While what you're saying seems theoretically possible, it also seems a long way off (perhaps several millennia).
You don't need oil to make plastic - you can literally make it out of air (although it's harder, all the atoms necessary are in air).
All types of energy are more or less interchangeable, If one runs out, switch to a different one.
Animals use resources they find. Humans create those resources.