Once you refine the stuff, you have to distribute it to its markets.
There are no existing networks of product pipelines in the area. Building such supporting infrastructure would amount to a bigger, more expensive project than building a new large-scale refinery.
Thus, the most economical procedure is the crude oil pipeline to Texas (Keystone), where the refineries are, thence distribution to the rest of the nation via the existing product pipeline network.
Thanks. Sometimes us Non-oil folks don’t have a clue.