If you refuse to consider someone for something (anything!) based on their race, then, by definition, that is race-based discrimination.

I think many people are a lot more tolerant of discrimination in dating, though, even if it's (IMO) unfortunate. People who don't date outside their race are really closing their minds and their worlds to a lot of potentially great possibilities. I get that many people do it because of parental approval/disapproval, and I can absolutely understand the desire not to piss off parents in that way, but it's still a shame.