I believe what you're referring to is the Availability heuristic, the psychological phenomenon by which subjects search for, and recognize faster, patterns that they've already encountered. The spillover into UX is that designs which follow patterns that are already likely to be familiar are (generally) perceived to be friendlier/easier to navigate.
A prime example is Amazon's (now discontinued) use of note tabs for section/location prompts. This was a shortcut for users that may not have been highly familiar with web navigation. By mimicking a notebook (something that's probably now less familiar to the current generation than web navigation was to the previous one) navigating the complex information hierarchy of Amazon become more intuitive.
The downside to this, as you've already touched on, is that breaking this habit for something that's potentially superior is a problem. Humans are creatures of habit, and once a pattern is established it can be damn hard to break it (why else woudl the vast majority of us still be using QWERTY keyboards over the more efficient DVORAK?).
Photoshop/Gimp's interfaces may not be the most intuitive in the world but they work, and many of us have invested enough time in them that they're now what we expect and accept as the most intuitive approach, but only as a consequence of exposure and pattern recognition.