Obviously revenue is not based solely on attendance, or the Angels payroll (if based on revenue) would be higher than Boston's. Boston is hampered by having one of the smallest park capacities in baseball at just over 39,000, but that hasn't hindered their ability to generate revenue. With the New England Sports Network (NESN), Boston's regional sports network is one of the highest revenue generating networks in sports, the Red Sox have a revenue source few other teams can match. But how does this relate to east coast/west coast bias?
No one can deny the east coast teams receive more media coverage than their west coast counterparts, but I doubt it's because of some sinister plan by ESPN or the other sports media outlets. It's because of time. When west coast games end, most fans in the central or eastern time zones are sleeping, having already been updated on scores and news. Have the Boston Red Sox benefited from this? Absolutely. Has the east coast bias hindered the Angels? I don't think so. With more coverage the Angels would probably generate a bit more revenue and have a slightly higher payroll, but the important thing for a team's success is its ownership and team management. Since Arte Moreno has taken over ownership of the Angels, they have succeeded in spite of any biases there might be in the media.