What I am thinking of doing for the outdoor weather station I will someday get around to finishing is to have it be on a separate WiFi network. To get data from it you will have to connect to that WiFi network.
Inside the house, I'll have an RPi or something like that which has WiFi and Ethernet that will use its WiFi to connect to the weather station's network and Ethernet to connect to my home LAN.
If someone steals the weather station, the only password they get is the password to the weather station network, assuming that it has one (not sure yet...may make it open so that anyone in WiFi range can connect and read the data).
Same thing for the automatic wildlife camera I'm contemplating. Probably that will go on the same WiFi network as the weather station.