NEW YORK (AP) - Many Americans appear to be watching the annual holiday spending ritual from the sidelines this year. Money is tight for some. Others are fed up with commercialism. Still others are waiting for bigger bargains. And some are just more thoughtful about purchases. Used to be, stores counted on Americans to spend during the holidays. But this year, some are scaling back - or abstaining completely - from the U.S. year-end spending frenzy. Sales so far since the official kickoff of the season on Thanksgiving have been disappointing. That's bad news for retailers, which depend on the holiday season for up to 40 percent of their revenue. It also points to shifts in the attitudes of U.S. shoppers that could force stores to reshape their strategies.