The England man's ankle injury forced him to miss his new team's stunning 6-5 SuperLiga tournament win at Dallas.
But furious home fans paraded banners reading: 'David - welcome to America, where people like you get paid to do nothing.'
Eight of the Galaxy's remaining 11 away games are already sold out and the other three, all in big gridiron stadiums that hold 60,000-plus, have sold 40,000 tickets so far.
LA boss Frank Yallop insisted: "David is desperate to play and I can see the fans' disappointment. But they have to realise he is only human."