Yeah, my understanding is that there's a couple of moving parts for that:
- Methane is 28x more potent as a greenhouse gas than CO2 is. I'm rusty on my chemistry but it seems like CH4 + 2 O2 => CO2 + 2 H2O, so by flaring it you're getting a 28x reduction in GHG potential even though it looks bad seeing it burning like that.
- The infrastructure isn't in place to harvest, liquify, and transport methane from oil fields. Oil itself is relatively easy to transport away from oil fields to refineries, while natural gas needs near-site processing to turn it into a liquid and keep it compressed. You also would need to build out (smaller) pipelines to transport it from the oil field to the existing natural gas handling infrastructure which may not be nearby.
It's one of those things where it's basically free coming out of the well but a big investment would be required to capture it and, assuming you're going to be pulling the oil out anyway, burning it is better for the environment than just venting it.
Edit: I do recall recently reading about some tech though where they were going to start using it on-site for fuel for equipment. I think it was for on-site generators instead of using electricity from the grid, but I don't have a link handy.
That would be Giga Energy.[1] They co-locate containerized Bitcoin mining systems with wells that produce excess natural gas and methane, burn the gas for power, and export bitcoin. Really.
That would kinda suck as a user as these things are notorious for switching on and off as gas is available (which isn't constant). For bitcoin miners that doesn't matter, but if I was running a long compute job...
Flaring is more cost effective at current prices