D&D and Pathfinder despite all the change are still dungeon based adventures, where treasure collection is a central part of the story, which are kept in treasure chest. Pathfinder has done a lot to make those dungeon look other things. But in the end paradigm is the same, regardless if you call a dungeon a town a series of boats, or even hex grid. But Shadowruns, generally aren't dungeon crawls, most involve people to some degree, extracting them, moving them, maybe assassinating them, lewt isn't kept in chests, and loot other then the pay day is discouraged. Sure you could have a shadowrun to go find some weird genetic changeling but let me just tell you it's not going to hard for SR team to spot a mimic in the D&D sense. Most runners will have thermal vision, which would probably give away your mimic right there, but even if that was managed disguise that somehow, there is no getting around it having a living aura, so mages will spot it easily. In the end you can put death trap and automated defense into SR are lot more easily then a weird object shapeshifters.