I notice Zafir beat me to the punch and most of what I say is redundant (and they say it better) but I had to look a few things up (including a visit to my dear old friend, the Russian eShop).
Because they like to have fixed prices that don't fluctuate every few months? I could ask you as well why you are still profiting from the cheap British prices for VC games that have been set during the Wii era when the value of the Pound was much higher.
N64 VC releases are £9. £2 more than their Wii versions. So it was NES and SNES only. I imagine those were set at the Wii VC prices because the disparity was so big it would be cheaper to buy via the Wii Shop and pay the upgrade fee (as is the case for N64 games). I guess when the N64 VC rolled into town somebody forgot that.
But here is some food for thought.
They have changed exchange rates for other countries in the last few years. Here we go:
:AUD used to be 1:1.5 it is now 1:1.3
:ZAR used to be 1:10 it is now 1:12
:RUB used to be 1:50 then 1:40* it is now 1:75 (however some third party games were kept at the older price point...also this massive hike it currently cheaper than the UK prices).
*-Looking at FE Awakening DLC (which for some reason also is frozen in time). Apotheosis DLC is 79 while the other single DLC are 99. So that turning point was somewhere around there.
While most of those are up Australia was down. I do not think 1=£0.90 last seen in the real world for a reasonable amount of time back 2008 (and set when the DSi came out) is at all fair. Would people still be complaining if they went for 1=£0.85 or ever £0.80? Absolutely, but at least you could look at a chart and go, yeah I see your point rather than look at a chart and see that NOE have taken the highest possible value and chosen to make no changes despite making changes to other currencies based on smaller timescales (and also not basing all non currencies on this metric).
If you are bothered so much by it, just use an -store. Goddamnit.
If that person fucked over their 3DS by locking themselves into the UK eShop thanks to NNID being designed badly they actually can't do that. The nearest they can do is have a second system (with no NNID attached) and do a system transfer whenever a purchase is made to assimilate that purchase (good thing the transfer limit was dropped). Also see earlier about what I said about New 3DS not being able to transfer back to old.
As for Wii U. Some people might not enjoy having several users in different currencies and won't be prepared for a fight if their system does break. If Nintendo UK are fairly bad at restoring UK NNID I can see them being assholes on purpose towards non-£ ones and be like "hurr hurr the French NNID will need you to contact French customer services" (despite the fact Germany handles all account stuff anyway and hence it should make no difference).
I do use the cheapest currency of the month as the system allows (I probably would just not use the eShop if it did not or just import the hardware outright). I feel by complaining I am representing the silent majority who do (or can) not.