You know what just occurred to me?
Concerned people sensibly prepping and stockpiling for disruption will probably have a positive impact on first quarter retail figures.
And if that happens, Leavers will be delightedly grabbing at these as "evidence" that Brexit is Great for the economy and shows vast consumer confidence in the Sunlit Uplands (rather than the opposite).
Whilst conveniently forgetting that they'd spend considerable effort in exhorting people not to prep because it was all rubbish hysteria/panic/scaremongering/selfishness/wastefulness and all this lack of faith was killing Brexit fairies, etc.
(Plus, I suspect, most Leavers too have been stashing stuff away in a classic "do as I say, not as I do").