There's no limit to what a kitchen towel might sop up throughout the week, so washing your towels separately from regular loads of laundry ensures that no germs or leftover food particles end up on your favourite set of pajamas. If throwing only a couple towels in the laundry machine seems like a waste of water to you, I get it. In cases where dish towels are lightly used and haven't touched any questionable surfaces, they can be mixed in with a regular load of laundry to save time and water.