I bought some shoes from a drug dealer.

This joke is a masterclass in wordplay, perfectly blending two very different scenarios into one hilarious punchline. The humor hinges on a clever double entendre. When you hear "laced them with," your mind initially goes to the literal act of putting shoelaces into shoes. However, the mention of a "drug dealer" immediately primes you for the other, more illicit meaning of "lacing" something – that is, adding a psychoactive substance to it. This sets up the perfect misdirection (Review).

The payoff comes with "tripping all day." In the context of poorly-laced shoes, "tripping" implies stumbling and falling. But because we're talking about a drug dealer, the more potent and humorous interpretation is "tripping" as in experiencing the hallucinogenic effects of drugs. The joke's genius lies in how it seamlessly pivots between these two meanings, exploiting our expectations and delivering a surprising, yet perfectly logical (within the joke's twisted logic) conclusion. It's a classic example of a pun that relies on common slang and everyday actions to create a laugh.