Uller
Adventurer
It seems to me to be equally arbitrary to assume that the world is full of high-level npcs capable of crafting or stealing the exact item you want and magic shops that stock such an item.
Oh sure. Where I'm coming from is I've seen some designers mention (can't find it...so maybe I'm hallucinating here anyway) and a few commenters here and there also say that magic items shouldn't be buyable. I think the rules should be neutral on this point and they should just give good guidance to DMs on how to control magic items in their games. Every game I've ever played in, it's been about 50/50.
My understanding is the default world is Forgotten Realms (meh...). It's hard to imagine FR without a magic shop in just about every city (I'm playing Baldur's Gate EE right now...sure enough, even the Feldpost Inn has a few +1 weapons and such for sale and as my party is getting to be about 3rd level I will use the 8,000 gp I have to outfit each of my PCs with either a +1 weapon or +1 armor).
for me, the really cool, top of the power curve type items for the PCs level are not available to buy in most cases. Those, you have to find (besides, the PCs almost never have enough gold to buy them anyway). For lower level items, this isn't the case.
So far with Next, We've just be staying away from magic items for the most part anyway except for ones that do weird things. In our Isle of Dread campaign, they have a ring of water walking, a +1 Sword that detecst gems (I think) and a wand of levitation. Each player makes good creative use of them and it's fun. Obviously when you are stranded on a primitive island there is no magic (or any other shop) around anyway...like you, I kind of have fun no matter what.