People who live in glass houses shouldn't throw stones" is not about hypocrisy but about vulnerability. There is no suggestion of 'the same kind of fault' in the verbal image we are given. To be about hypocrisy it would have to be something like "People who live in glass houses shouldn't throw stones at other people's glass houses" perhaps, or "People who live in glass houses shouldn't say it's wrong to throw stones, and then do so anyway". The pot, in this saying, doesn't call the kettle black.