Wait, people actually pay retail price for Plus and Gold??
Why don't you just stock up on Black Friday?
Just want to point out that while that's good for some regions, this simply doesn't work elsewhere for PlayStation Plus. When I was an Xbox Live member (it may have changed since) there was no issue in doing this since deals online were available rather plentifully, deals could regularly be found, and as far as I recall the precise region didn't matter (if it did it was easier to find Irish codes, but I can vaguely remember buying UK codes).
On PS+, retail stores don't tend to regularly (it would be rare) discount Playstaion Plus Subscriptions, online stores stocking Irish cards are rare and since we have to use Amazon.co.uk (which stocks UK codes that don't work in Ireland) discounts can be very tricky to find. If the codes were locked by continent it would be easier to find a deal and I would agree that it would be more sensible to stock up on discounts, but when they are locked in an even more restrictive way there are some places where deals are not easy to find (now admittedly I've only been a PS+ member a very short time, because for me the service was never truly worth the cost and I've only bought it hesitantly after getting a PS4 to play online, so it's possible I have just been unable to find a very cheap source of subscriptions online or cheap deals on irish codes, but I have tried to keep an eye-out for them and I simply cannot remember a regular or consistent deal on them).
Edit: I see there's also another thread on the matter so I'm unsure of perhaps this is more appropriate for that thread which seems more general than the Uk, but either way this strategy is problematic in certain areas.