If someone has the resources to obtain your Wi-Fi password from Google and is determined enough to get within range of your network, you're being targeted by a very dedicated adversary. Things like physical security, TEMPEST and listening devices become valid concerns. This is a highly unlikely adversary for the majority of internet users.
Note that non-targeted attacks (the type that leak password lists) are not a serious threat here.
That's not necessarily true. I imagine the data would most likely be targeted by a third party that's disinterested in you, but very interested in your adversary's money. I wonder what the going rate rate for all the WiFi passwords on my block would be. Or neighborhood. Or zip code.
Note that non-targeted attacks (the type that leak password lists) are not a serious threat here.