The kinds of attacks that makes regular password changing a good idea become a lot more unfeasable when applied to real locks. Infact the only comparable attack of this nature that is feasable is stealing said key and using it as soon as possible. Now sure, you could make a copy of said key, but that takes time and money, and every moment you spend without the key and owner being reunited has the risk of the owner noticing the key is missing, making it much harder to diffuse the situation without getting caught. You also cannot brute force a lock by trying to use hundreds of thousands of keys as that would take forever, look very conspicuous and will eventually get you caught. Using lockpicks would be much more practical here but it would still look suspicious and changing the locks isn't going to help here unless the attacker has picked this lock before. There's also the fact that changing passwords cost nothing, whereas replacing locks takes time and materials, which end up comparatively costly.