If you're on the Internet, chances are you love discussing '90s nostaglia (sorry, but the Internet was invented for people who know all the words to LFO's "Summer Girls" and watched TRL after school). This means that you'll probably be interested in an essay on the racial implications of Nickelodeon's Doug.
See, Doug Funnie was a walking, talking Caucasian stereotype, closet full of sweater vests and all. But, Doug was the only person of real world skin color in the Bluffington universe. Everyone else was purple or green or some other outlandish color. A new book, Slimed!: An Oral History of Nickelodeon's Golden Age—due out in September—explains why Doug's universe was so... diverse.
In Slimed, the show's executive producer Doug Campbell explains the unique coloring decision: “Look, we’re not black people, we’re not Mexican, but we want the cartoon to speak to all groups. How do we get past the barrier or ethnicity? And Jim said, ‘Let’s try coloring them all different colors.’”that Doug was white because Nickelodeon's founders wanted to cater to kids with cable and, to them, that meant white kids.
Furthermore, Slimed! goes on to explain that Doug's the only white kid in his own show because Nickelodeon was trying to cater to kids with cable. And by "kids with cable" they mean white kids.