[MBCook]

Again, I don’t know the actual reason, just that it’s clearly legal.

Many people are very allergic to pets or scared of them and won’t live in a building/complex if there are animals there. If you’re a landlord and you allow pets you also have to deal with any possible damage they may do to your property, even though you can make the renter reimburse you for that.

It may be that because of those factors courts have determined that it’s perfectly reasonable for landlords to choose not to allow pets no matter what effect that may have on the number of people of different races who apply to their properties.