It doesn’t come from dinosaurs. It was formed from the organic components of plankton and algae, and significantly predate the dinosaurs.
Plus check out this fun fact:
Biologists set out to estimate the total biomass of phytoplankton and calculated that less than one billion tonnes of the single-celled microorganisms were alive in the ocean at any one time. There were 45 billion tonnes of new phytoplankton each year, 45 times more than their own mass at any given time.
The point being is that that’s a lot of plankton corpses. And that’s leaving out all of the other microorganisms.
So we can either blame ourselves, or we can blame that first cascade of chemical reactions we would come to see as “life.” At an almost immediate instant in time it died and turned itself into sweet, sweet oil and set the chain in its inevitable motion. Either way, the dinosaurs had nothing to do with it. They just hung out until they got flying down - although even there they’ve been a bit liberal in their applications - and they’re all around us.
Unless you have outdoor cats, in which case you are a dinosaur hater.
Seriously, though, keep your cats inside. Cars, dogs, and poison make for a rough life.