Patrick gives detailed descriptions of each character's clothes, including brand names and prices. Readers who are extremely knowledgeable about 80's fashion will notice that the outfits are clownishly mismatched.
There's a similar gag involving the food at the various restaurants, which go from outrageous but plausible (red snapper pizza) to outright inedible (mud soup and charcoal arugula).
In the film there's also "peanut butter soup". You don't have to be a genius to be weirded out by that one (peanut soup, sometimes using peanut butter to speed up cooking, does exist though— and is quite tasty).
Technology Marches On: Patrick's state-of-the-art home entertainment toys seem a bit quaint when read now.