I remember rewatching T2 on computer after seeing stan winston studio showing props. The movie shows a lot of these physical props for very small frame numbers. Very hard to notice if you slow things down but at normal speed it just flows through the context of the scene. It's a minimal amount of detail that your brain needs to have to accept continuation. Probably a byproduct of the time.. can't CGI all the things so you have to optimize and find the best bang for your bucks in every dimension.