My other idea (can't remember where I saw it now) was to make a 7-layer dip in a rectangle casserole, and top with guacamole, using sour cream in a piping bag to decorate like a playing field, with olives decorated like footballs on top, and pretzel sticks for the goalposts.
This football field idea sounds so cute! Do you know where I could get the directions and/or a pic?