SAN FRANCISCO — San Francisco police say 75 hotel workers protesting outside the J. W. Marriott’s Westin St. Francis hotel on Labor Day were arrested for blocking a street in one of the city’s busiest tourist areas. Unite Here Local 2 spokesman Ted Waechter says about 900 Marriott hotel workers demonstrated Monday at Union Square as they consider a vote to authorize a strike. He says 8,000 workers in more than 50 hotels in San Francisco and six other North American cities are working without a contract. Waechter says many hotel workers hold two jobs to support their families and their salaries have increased by 7 percent in a decade. San Francisco Police spokeswoman Officer Grace Gatpandan says those arrested face misdemeanor charges of failing to obey a police officer. Marriott did not immediately respond to an email seeking comment.