Why are straight white entertainers acting gay to be funny?

I noticed that when James Franco was roasted by his friends like Seth Rogan and Jonah Hill last year, there were so many gay jokes even Aziz Ansari acknowledged it.James Franco then made gay jokes about himself. Johnny Depp kissed Jimmy Kimmel twice on Kimmel's talk show. People were offended when Will Smith slapped the reporter who tried to kiss him and called Will Smith homophobic for getting upset. Then you have old school greats like Kevin Costner and Morgan Freeman coming on the talk shows and you can tell they looked uncomfortable with for instance Craig Fergurson touching the top of Costner's knee. You also have the Jimmy Fallon and Justin Timberlake bromance. Will Ferrell also does it alot with his crew along with Jon Stewart, Stephen Colbert, and Conan. I think guy friendships are great but why are all the comedians constantly making gay jokes about one another, kissing one another, and talking about how attractive they are to one another. I guess it is supposed to be funny, but they do it on a regular basis.If a male guest goes along with the behavior, they are cool. But when a male guest is uncomfortable with it or not that affectionate with another man, he is considered homophobic. Is it just a white people thing that white people find funny because I don't hear alot of gay jokes in other races just stereotypical ones ? Just wondering.