Why do you think shielding is bad! Shielding of what occurs in a volume surrounded by metal?
In the case of a room lined with metal, there is certainly shielding of the inside of the room from outside radio waves. That is, radio signals from radio and TV stations, cellular stations, signals from various special services, etc. are less likely to penetrate inside. This is observed, as you say, in stores clad with metal siding.
But a similar effect, as mentioned above, occurs in homes made of any material. Somewhere more, somewhere less.
So it is not the shielding that you have to fear, but the lack of it.