A lot of the positives of DC's shop system are lost if XP is no longer a factor in how combat effective you are.
Yes, DC has leveling, but it's far more a gear-based game than a leveling-based game.
DC uses leveling more as a means of controlling access to gear and providing access to different difficulty tiers, rather than simply a means to overcome challenge by out-leveling it. Some support for that line of thinking is that:
-the various difficulties are capped at various levels. You cannot level up beyond the cap for that difficulty.
-But, if you have a character that is above the level cap for the present difficulty, your stats are scaled to fit. You are still stronger to whatever degree, but not in the "planetary annihilation" sense that we get from other RPGs where you level-up to win.
-Stat gains via leveling are of significantly lesser importance. Gains extremely small and sparse (like, you might get +1 strength for your sword guy like, once in 3 levelups, and a point in luck and int somewhere in between)
-The efficacy of gear dwarfs whatever you can accomplish through merely leveling, encouraging players to play around with gear. You might have a weapon that pumps up damage %50, but then another weapon that flatout adds X-amount strength to your person while it's equipped. Then, consider that gear can have 1 to 7-ish different modifiers on it, and at that point, grinding XP just to get stronger is hardly worth even being an afterthought- especially when at end game, you have nothing really restricting you from using whatever gear you wish.
And that's just the gear side. I already talked about the item side, and how it makes consumables useful through a mix of stocks, restocks, and well-thought-out effects, none of which are affected by whether or not you level up, or that the game allows experience points.
But let's ignore stat gains through leveling up and for argument's sake, say that the character in
'Under-Development Indie RPG' was at base stats forever. A consumable that lets me hit harder for 60 seconds, or a piece of gear that makes skeletons hit me less hard, or a trinket that gives me another stock of my fancy-move... those things can be useful, depending on the game. And such is the case with
Dragon's Crown.
But let's look at
Indivisible specifically: there's so much we don't know about systems, gear, combat, exploration items... that it's rather bold to definitively say that buying gear has no place in a game like that. It's more a matter of figuring out what gear makes sense (and whether or not you want gear in the game anyway), and what consumable items make sense.
For example, let's say that game has '
story-based traversal shoryuken move' thanks to finding some artifact during the adventure. Some possible item-based, or gear-based, modifications can be: now it's on fire, doing multiple hits on the way up; Now it's electricity and puts folks in a brief stun; Now it's armored for 1 or 2 hits; Now dollar-bills rain down around you when you land; Or maybe it just does flat-out %X higher damage, with Y-tradeoff.
It's a matter of approach. If I had to pick a
tldr, it would be that shops and gear don't have to suck, and while not absolutely necessary, they can still be worked to fit a variety of game contexts if so desired.