Actually Dave Chappelle is an alien from Planet Gersavnod and he's actually a green alien but they painted him brown before he landed on Earth. He likes to eat banannas on earth and he hang's out with the K-Pax guy. They actually are lovers; Chappelle plays role of the slave, naturally (brown). I enjoy cotton candy now and again, sure; who doesn't?
He is here to study DP and it's related symptoms. SoulBrotha is right; he obtained the mental affliction after smoking some of the African reefer somewhere in the jungle. Problem was, this particular reefer plant had a few ounces of bamboo feces on it, and the chemical combination was too overwhelming for our alien's brain. The result -- DP, and the subsequent hospital stay.
They feed him bannana's at this particular African hospital. Once a nurse named Janice brought him a cucumber instead and he slit her throat. Aliens aren't always benign HAVE YOU SEEN INDEPENDENCE DAY?