You should probably check with the chair of your department. In general, you have more leeway in college courses. I teach an evening class in a community college. Most of my students work full time during the day. I bring something to eat myself before class. But I let my students know that if they bring something, they must clean up their own messes. My dean doesn't care unless he gets complaints from the cleaning crew. The classroom usually has a large wastepaper basket with a liner, and I haven't had any complaints from the cleaning people or the dean in four semesters.