Background: Williams was born in Nassau, The Bahamas, on November 12, 1874, to Frederick Williams Jr. and his wife Julia. At the age of 11, Bert permanently emigrated with his parents, moving to Florida. The family later moved to Riverside, California, where he graduated from Riverside High School. In 1893, while still a teenager, he joined different West Coast minstrel shows, including Martin and Selig's Mastodon Minstrels, where he first met his future professional partner, George Walker.
Context: Walker was in ill health by this point due to syphilis, which was then incurable. In January 1909 he suffered a stroke onstage while singing, and was forced to drop out of Bandanna Land the following month. The famous pair never performed in public again, and Walker died less than two years later. Walker had been the businessman and public spokesman for the duo. His absence left Williams professionally adrift.  After 16 years as half of a duo, Williams needed to reestablish himself as a solo act. In May 1909 he returned to Hammerstein's Victoria Theater and the high-class vaudeville circuit. His new act consisted of several songs, comic monologues in dialect, and a concluding dance. He received top billing and a high salary, but "the White Rats," an organization of vaudevillians opposed to encroachments from blacks and women, intimidated the theater managers into reducing Williams' billing. The brash Walker would have resisted such an insult to his star status, but the more reserved Williams did not protest. Allies were few; big-time vaudeville managers were fearful of attracting a disproportionate number of black audience members and thus allowed only one black act per bill. Due to his skin, Williams typically travelled, ate and lodged separately from the rest of his fellow performers, increasing his sense of isolation following the loss of Walker.  Williams next starred as Mr. Lode of Koal, a farce about a kidnapped king that was well received by critics as a star vehicle though not a fully realized storyline. Camille Forbes' Introducing Bert Williams collects several reviews with competing race-based agendas. Many of the white reviewers praised Williams' "apparent spontaneous," "unpremeditated" humor, as if he were a guileless simpleton in no control of his own performance. A Chicago critic wrote, "They are racial, those hands and feet," while a Boston reviewer felt that the show's flimsiness and lack of structure were actually attributes because "when we succumb to the surreptitious desire for the broad tang of "nigger" humor, we want no disturbing atom of intelligence busy-bodying about." Meanwhile, many black reviewers ignored the show's faults, praising Williams' continued persistence and prominence as much if not more than his actual performance; an Indianapolis reviewer thought the play was evidence that "we are nearing the day of better things." Despite the good if loaded notices, Mr. Lode of Koal played a secondary string of theaters and was a box office flop.  Following the show's abbreviated run, Williams returned to the vaudeville circuit, and "the White Rats" renewed their opposition to his featured status. The Victoria Theater responded by cutting Williams to secondary billing, but putting his name on the marquee in lettering twice as large as that of the nominal headliner. Newspapers took note of the disingenuous manner in which the White Rats' demands had been met, as well as the way in which many of those performers who were impeding his career would rush to the front of the theater whenever his turn to perform came up.
Question: Why?. Whats the answer?
big-time vaudeville managers were fearful of attracting a disproportionate number of black audience members