The only things I can think of are those checked or striped pants that chefs wear, and Carhartt-style non-jean colored canvas pants or painters' pants.
I second the Carhartt/Dickies suggestion. Those are designed to get dirty. Although, I'm a cook and find that the heavier material they're made of gets a little too warm. I just buy pants from Old Navy, usually, which can be had for less than 5 bucks on sale.