The reason a casino puts their logo on the slot cup is so that you will walk around to other casinos with their cup advertising their casino. It is OK to take slot cups, consider them in the same light as matches. In fact we want you to take our slot cup. "Hey, look Marge that person has a slot cup from Harrah's filled with coins, the slots must be hitting there, lets go try our luck there."

I worked in the gaming business on and off since 1981 and have never seen security tackle and arrest anyone for taking a slot cup. "Hey buddy did anyone give you permission to take that from our property?"