$5.5 billion ... that's how much money fast-food restaurants made on the sale of kids' meals last year.   It's certainly a huge chunk of the fast-food pie. Think the kids are begging for those meals because they love the food? Think again.

 According to researcher NPD Group, nothing gets kids more excited about eating out than a kids' meal with a toy. Their polls found that 36 percent of kids under age 6 say the toys are their favorite part about eating out. That compares with 16 percent who like the food best.

Of course, the fast food giants already know this. That's why they give away toys with every meal. But in one California city, they may not be able to do that for much longer.

In San Francisco, newly proposed legislation would ban toys from most kids' meals sold at McDonald's, Burger King and other chains unless the meals meet more stringent calorie and sodium limits. The legislation also would require fruit or veggies in each meal.

If this legislation passes, San Francisco would become the biggest city to draw a line in the sand around kids' meal toys and childhood nutrition. Several months ago, Santa Clara County, just south of San Francisco, became the first local government to enact such a law, but it applies to a tiny number of restaurants. In San Francisco, this legislation could affect hundreds.

San Fran takes on Happy Meal toys
California city is set to become the largest city to limit popular toys in kids' meals.