I didn't vote for Lee, but I applaud his effort. Why not take the revenues of hatred and use them in a way that will mitigate the hateful message?
SF could have decided not to take advocacy ads on its buses at all (and would have passed constitutional muster as long as it was even-handed and rejected all point-of-view advertising).
Instead it chose to accept the ads and use the revenue in a manner within its discretion that communicates that it is not the official sponsor of such bile. I think that was a responsible decision.