My guess is that Ford, or Delos, or the conflict between them is creating such a mess that nobody is paying attention to the what the low-level scrubs are doing. It barely registers on the scale (even if it should). Hell, a lot of the other mistakes with the hosts would find their way through if it wasn't for curious employees like Elsie investigating. I know that stories like these tend to only focus on the important characters, but Westworld seems vastly understaffed, or at least a lot of said staff is kept in the dark. Perhaps this is to do with Ford consolidating control and the (illusion?) of power, or perhaps it is because Westworld seems to be bleeding money.
tl, dr: The techs can get away with what they're doing because Westworld is actually a fucking mess right now even when everyone thinks they're in control.