if i had that job i'd take a small object from each house i cleaned. nothing major, but i'd sell em on ebay or something for a dollar and over a long time you'd make quite a bit of money and no single person would lose anything of value to them haha
but for me its usually just work. then sneak beers into the dairy cooler in the basement, chill in there, eat lunch, see how long i can get away with chilling in the bathroom for, mess with the other guys, and walk around aimlessly. then again... i almost got fired last summer (summer job) so this year i'm gonna put in some effort, stay after hours for that 1.5 times pay, and make some solid money hopefully.