In Jurassic Park (1993), there is a rather iconic scene wherein the blood-sucking lawyer gets eaten by the T-Rex while sitting on a toilet.
Earlier in the movie when Grant, Sattler, and others exit the vehicles to get a closer look at the triceratops, Muldoon, Hammond, and Arnold get annoyed that they left the vehicles and say that they are going to get locks to keep people in the SUVs. With this in mind, it seems strange that there would be a toilet near the T-Rex paddock since guests should not be able to use it (because they should be locked in). If it were only intended for employees, then I would have expected only a porta-potty, not a full-flush toilet that requires working plumbing running to and from that location.
Is there an in-universe explanation for this toilet's location? I realize the out-of-universe explanation is that it adds a bit of humor to an otherwise tense scene.