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Starbucks isn't handing Splash Sticks out like free candy. (Why would they? Nothing is ever free at Starbucks).

After a few experiences it appears that the Splash Sticks need to be "requested". If you order a drink or not ask your barista for a Splash Stick. I have also heard that they are passing out sticks for large orders.

It may work out better and be a bit more entertaining if you order a drink and struggle asking in desperation for a splash stick.

If you choose not to order a drink, simply request a splash stick for experimental purposes.

Once it's in your hand - take it on an adventure.