I would guess some combination of feeling various minorities were filthy and not wanting to deal with them, and a network effect. Sure, you might make money let

I would guess some combination of feeling various minorities were filthy and not wanting to deal with them, and a network effect. Sure, you might make money letting rooms to a handful of blacks but you would likely then lose out on all the other racist white folk who don't want to use the same sheets as "one of those people". One can easily imagine it might have been economically harmful to NOT be a racist in those days.