You can't reason anyone out of a position they didn't reason themselves into in the first place.
A funny thing about all this, the D.C. council is doing their political best to get votes here. All WalMart is doing is reacting to the events, nothing personal, no emotion or politics about it. They even had the courtesy to let the council know beforehand what their business plans were.
That discriminatory government action doesn't fit their plans. So they'll open stores just outside of D.C., no big deal. The people in D.C. will have to go out of their way to get there, just an added inconvenience they can thank the council for. Oh, and drive further for a job, if they can. Or someone else will get the job.