Surely the pouch or box is just for safe storage when the key is in the house and unattended. If you are going out then you would just take the key and put in in your pocket or bag as normal? The issue isn't people trying to steal/extend the RF range when the key is on you, it's mainly at night when the keys are in the house and potentially unattended.
There's been a couple of car thefts round my way recently and it's been "un-intrusive" (for want of a better phrase) theft where keys have been left close to doors etc.
My car key is in a box somewhere upstairs in my house and I rarely use it as my phone acts as my key. So a thief would need to know to take my phone instead (oops!

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