Using casino chips or slot tickets for tipping...

I give cash + whatever change I have from the day. It's always more than 4 bucks and the extra towels I get shows that they were appreciative

 

I actually also got a new shiny non Sacagawea coin that I had never seen before on our last trip.

 

I tip with cash. Housekeeping, cocktail waitress and restaurant staff are putting in a lot of work, so I give them something they can immediately put in their pocket and not have to put effort into to get the money.
For a room cleaning tip, I leave a crisp-looking $5 bill as a subliminal influence towards neatness; a tatty $5 bill gives the wrong impression for keeping the room neat and clean.

 

Just tipping in cash. Everything other is an expression of laziness, that I don't accept in myself and (to a lesser extent) my room service. Good service deserves respect. And slot ticktes or chips, not cashed out, deserve to be a souvenir. Or a reason to come back.

 

Definitely a nice sentiment. That said, even if you're not doing it, tons of people tip housekeeping and waitresses with chips, and it's not like they have to be individually redeemed, so you're not really saving them much effort. They're still doing a stop by that window at the end of the shift no matter what. Slot tickets are a different story, because each one needs to be independently scanned. But I can tell you first-hand that most front-of-house workers could not care less whether you tip in cash or chips.

 

I would tip in cash, not in ticket vouchers. Who wants to go to a machine with a bunch of ticket vouchers and put in ticket after ticket to finally cash their tips or go to the cashier and the cashier would have to scan every ticket? That takes up a lot of time and the bosses would not be happy about that.