I'm asking this because I watched an iconic scene from a classic Filipino comedy film, Father en Son. In the aforementioned scene, the main character is filming a whiskey commercial, but the whiskey itself tastes so strong that he kept flubbing his takes. It came to the point where, in the final take, he's so drunk that he said his in-universe lines wrong and ended the ad with a pointed remark on just how bad the whiskey he's advertising tastes like - all to the chagrin of the very disappointed director.

I know that it's a comedy film, so the main character drinking and getting drunk from the whiskey is part of the joke. However, I'm wondering if, in reality, actors whose characters are shown drinking liquor (especially in advertisements that sell liquor) really are drinking alcohol or if they're having "liquor-colored" water instead.