The term store comes straight from the show itself...
Charlie X: "They don't have any in the ship's stores."
Assignment Earth: "Have ship's stores prepare the proper costumes."
And the idea of stores on naval vessels is absolutely normal today
, and as I said, as a frontier ship, the Enterprise would be the only access to this type of stuff for outlying posts, which was also made very clear in the show...
Mudd's Women: "You're a long way out in space, gentlemen. You'll need medical help, cargo runs, starship protection."
The Man Trap: "Our mission, routine medical examination... of archaeologist Robert Crater and his wife Nancy."
Charlie X: "Anything we can do for you, Captain? Medical supplies, provisions?...
This must be a space first. A transport ship that doesn't need anything?"
On the subject of the Enterprise being a military ship
... while some people only see the military as sort of a live action
video game, and see no need for anything beyond point and shoot
for anything with a military label associated with it (sadly, our current president here in the US falls into this group), the military has had a long history of being more than just pawns of battles between warring nation states.
Basically, I look on the Enterprise as having a combination role similar to Captain Cook's ships (Discovery and Endeavour) and the US Coast Guard. Her position is policing outlying territories... and (like police) she isn't design to provoke engagements with anyone (the police don't drive around in tanks, though they are able to defend themselves). And she is designed to perform exploration.
While she may be ill suited for starship battles
type of gaming mindsets, she will be perfectly suited for the role she played in TOS (which, after all, is what I'm working towards).
So for those who want a blistering battle cruiser ready to fight, fight, FIGHT!
, these aren't the plans for you.
For "shopping" purposes I imagine it's usually more a case of the crew buying/trading things on shore leave than the other way around.
But that is the exact opposite of the role she plays... she doesn't travel from port to port to port, she is on the frontier. She is
civilization paying call to isolated posts and colonies. She is bringing those things to them, because they would have next to nothing on their own.
Today, on Earth, the navies of the world have no frontiers. Every port of call is pretty much a well settled community, with the exception being some places in the Arctic or Antarctic. That is why you have to put yourself back in the mindset of when much of the world was unknown. And what types of things would navies have provided back then (if they had the means).
The challenge in depicting (envisioning) a future is how far can you change things while not alienating/confusing your audience.
Our contemporary world would likely have little familiar to someone from 300 to a thousand years in the past. How much can things change over the 300 years? How much will remain familiar?
Actually, that is one reason for looking way back in our past. Would someone of the early 1500s feel totally out of place in the early 1800s? While we have had some major jumps in the last hundred years or so, most jumps like those in history are few and far between. I'm pretty sure that people of the 1960s would be rather disappointed with the world of today (which is far less different from their world than they thought it would be).
The things that would be most likely to change are the things that are least efficient.
But lets look at a real world example... watches.
Back in the late 70s and early 80s, people believe that digital watches were going to replace watches with hands... How many people here use a digital watch? I own four watches, not a single one is digital. I can't recall the last time I even noticed someone waring a digital watch. Sure, digital watches were a great fad, and they do have their place (when people need additional functions), but they didn't displace what has worked for the last few hundred years.
And while we are on the topic of time pieces, what would have been the biggest leap forward in navigation on ships during the sailing era? From our point of view most sailing ships looked alike, but functionally, the addition of accurate time pieces made getting from one place to another very accurate, and ships became more streamlined because they were less likely to miss their intended destination.