Best Buy doesn't care about people price checking GPS units, they care about people price checking HDMI cables. Watch for cell blockers to be installed near the cable isle.
Cell blockers are illegal in the US. Even when the power is very low, if there's enough circumstantial evidence to prove intent to interfere with a transmission, I think that's an $11,000 fine from the FCC.
Perfectly legal to install EM shielding or a Faraday cage. I bet you'd only have to install a few of them before the mobile companies agreed to block certain urls whenever they triangulated a phone as inside one of your stores.
I wonder how casinos get away with seemingly blocking cellphone signals. In my experience whenever you go near a slot machine or table game in a casino, cell signal drops to zero.
