No they aren't. Look at stand up comedy.
Every black stand up act is like this: Blacks do "x" the cool way, white people do "x" the corny way.
There were a few white acts that did racial jokes(sarah silverman, Zach Galifianakis, Tim Allen, and Gallagher too name a few), but they didn't get popular until they toned their acts down significantly. However, almost every black comedian uses the same "blacks cool, whites corny" routine, and the most successful ones were the most extreme (eddie murphy, Richard Prior or DL hughley)