People with particular eye colour aren't oppressed as much as people of particular skin color. By grouping users by location often denies them a chance to see and mingle with people of other races and that's what we would like to avoid with FindDate.
Less politically charged example with food.... If your service simply shows all the different kinds of food available, users will generally stick with whats familiar. If the algorithm is designed to show them mostly food they've never tried before you can counter that bias and increase the likelihood the user will try new foods.
In our case we show all kinds of food by default. The user has the choice of choosing familiar food types. If it's available it will be shown first, if not it again goes back to default mode. User preference still get's priority, but given a chance to try something new; we don't see much hesitation.