I bought digital. So my sale isn't shown with the regular sales. I wouldn't doubt in the least if there is lots of digital sales.

I've bought a LOT of digital games this gen too, so I could also believe it. This particular game I got the special edition, but others.

Saw those numbers earlier, but I can't stop being happy for it. Games like this deserve to achieve success, and hopefully they're already making their next JRPG for the NX. :P

You can add +1 to that number. I haven't connected my Wii U to the internet since buying and playing the game because it is a hassle as I use my mobile phone to tether internet to my devices and Nintendo devices rarely work well when it comes to updates via this method. Heck I didn't even download the packs. Even if 5% of people are like me that would add 15k to your 290k number. It is also based on the assumption that it includes both Europe, Others, and NA. There are probably plenty of people who just don't want to update the game since buying it.

I actually talked about this and how the constant disconnections from the servers influence on the final numbers in a later post. If you defeat Volkampf while offline, your victory won't be counted for the register, even if you access to the online services later.

There are many reasons to suppose that the guy is lacking at best 50K victories from other users. 

True enough, but then again you have to consider demographic qualities.  That subgroup of Nintendo fans, the purest of the purists, is not really who this game is targeted at and not likely to be who it would appeal to (despite Nintendo tossing out a recommendation to Zelda and Metroid fans, clever as that was :P ).   I have no doubt there is a very, very, very small group that litterally walks into Gamestop, looks on the back of the box, sees the Nintendo logo, and buys the game immediately.  But as has been pointed out many a time on the internet, such extreme loyalists are - in almost all cases - the smallest minority. 

Having played XCX quite a lot, I think it is safe to say that this game's main audience is the overlap, not the central core of the hardcore Nintendo loyalists.  And I say that as part of that overlap.  While I like my Kirby and Fire Emblem and Mario Kart and Splatoon, I was not drawn to the game cause of the Nintendo logo nor exclusively because Xenoblade Chronicles was really good.  I was drawn to it because of my experiences with Oblivion, Skyrim, Dragon Age Origins, basically RPGs in general, especially open world ones.  In fact, those games are why I played the first XC.  So yeah, I would definitely put most of the target audience (and most of the sales) to overlap, probably the PC and PS4 owners since it is A) a JRPG that B) has a lot of WRPG elements with a C) combat system familiar to westerners and definitely PC players plus D) an open world with tons of side content.  All elements popular on those platforms, only rarely having visited Nintendo platforms.  And while it is easy to say that hardcore Nintendo loyalists who never ever touch any other platform "miss" these experiences and thus gobble up whatever game offers them that shows up, you can't "miss" what you probably haven't had.  

Hm. If I start a new game and beat him again, will that increase his defeat count? I suppose if I switched to a different 'user,' it would.

Yes, that's why I think this data will be eventually more inaccurate.