Condensation occurs when warm air meets a cold surface. So the problem occurs when you bring a cold camera into a warm (and humid) house. If your room air is spring temps and relatively low humidity, and you take a glass jar out of the 40 F fridge and put it on the counter, you probably won't get condensation on it. You will get condensation if you take a glass jar out of the freezer, or if you take it out of the fridge into 90% RH Florida room air.
The idea about putting the camera in a plastic bag probably works if you do the operations in the right order. Put it in the fridge in an *open* plastic ziploc bag, so it fills with lower-humidity cool air. After the camera cools down, open the fridge, quickly seal the bag, take it out of the fridge, and test it before it warms up.
As I alluded above, you can test the procedure with a glass jar or similar before trying it on a camera.