It's not easier - as I understand it, the leaks are tiny amounts along the entire length of the pipelines. Getting an absolutely perfect seal is something that's expensive to do, whereas in theory the CO2 footprint of coal is concentrated and therefore much easier to capture.
In practice, doing either of those will spike the price of the energy, and the only reason to use them over renewables is their being cheap, so it won't happen.
I think fixing leaks is an easier task than reducing the coal CO2 footprint. We'll have to figure this out somehow anyways, because a lot of methane will be going into the atmosphere from thawing permafrost, both on land and in the seas.