I have been exposed to so much concrete in the past half century that I cannot stand to be near it.

Porous materials should not be near food preparation and surface coatings are a temporary solution. Only an integral sealer (mixed into the concrete) could be considered permanent but its expensive.

I think you will regret making your kitchen filled with concrete. Concrete has nothing to do with a "rustic adobe southwest" style. It will not look like the traditional masonry covered in stucco (which helped keep interiors cool); it will look like concrete. Concrete is also difficult to maintain. It can crack and/or pit.

Your imagining that concrete will achieve that style is analogous to people who thought their kitchen would look "Tuscan" when they faux painted the walls to look like a peeling Tuscan villa, and added black iron scrollwork all around. Concrete kitchen cabinets and counters will not achieve a rustic adobe look. You achieve it with floors of terra cotta or Saltillo, backsplash of Talavera tile, rustic wood cabinets, arched doorways, thick wood counter on an island.

Thank you each for your input. Perhaps I am on the wrong track then, and perhaps my description was lazy. Allow me to clarify a bit:

1. The faux tuscan distressed look that was en vogue about 15 years ago is the most laughable thing to me, so to think I'd be replicating that kind of silliness is disturbing! haha

2. To your point about rustic southwest, you are absolutely correct about the terra cotta and saltillo. So perhaps it was a poor use of that descriptor.

3. While our building material will largely be concrete, my intention was to pursue an efficient building strategy by building more out of concrete than just the walls (while we're there shotcreting it anyway).

So, the look we're aiming for can be encapsulated with the following pictures - regarding the vanity and kitchen cabinets pictured below (ESPECIALLY the bathroom vanity you see)

So is this not concrete? Can concrete not adequately lend itself to this kind of design?

I'm a very creative person, but i admit I am an inexperienced builder. Thank goodness for helpful communities like this!

There are ways to seal concrete used in garage floors and pools. Getting the right matte finish as in your pictures is where the development may be needed for your use. This satin finish one part epoxy is about $40/gallon. Seal-Krete Epoxy-Seal 1-part White Tintable Satin Concrete and Garage Floor Paint (5-Gallon) in the Garage Floor Paint department at Lowes.com

There are quartz and solid surface countertops in colors that give a look similar to concrete. Have you checked those out?

I considered real concrete, but decided quickly against it for a countertop (sooo many negative stories online). Also wouldn’t use a painted surface.

It is really hard to comment without knowing more about your structure..concrete elements can be very heavy unless you have a slab structure…we had concrete floors that we stained( not a difficult or expensive option).. our only regret was that we did not include in-floor heating as this was our summer home…this finish is just a mop and spread stain..covered with a mop on sealer…easy diy

Lots of color options in stain if you like a more solid color

But the whole point is that the OP said they want a “rustic adobe southwest” aesthetic. A concrete floor shown above and the photos the OP posted last week are not that. As I said, concrete would make a faux-adobe-southwest look, and I used the analogy of people absolutely convinced they were achieving a Tuscan aesthetic when it was in style 30 years ago.

My comment was really to point out that staining concrete was a simple ..easy…inexpensive diy ….most people who do this choose the one tone terra cotta color..which looks very southwestern when finished…I spent may winters in Mexico where most homes look like the examples above…but i covered the counters with wood slabs for a more comfortable surface to work on..

Well to answer the OP's question - No to the idea of painted countertops. Not sure why you are saying masonry stain + good sealer is more $$$. That's the only thing that has any hope of working, surface coating would wear and peel off in no time. A skilled artisan, whether DIY or pro, could pull this off I think, but if an amateur I would consider other options.

ETA - it sounds like you are still in thinking/ planning stage, including very basic question of how you would build these structures and out of what material. As Im sure you already know, you are more likely to get help on websites devoted to green build and natural historical building materials/ methods - so many here are gonna shoot down anything outside the typical houzz/ hgtv box rather than offer any constructive advice. I do agree with the thoughts above that using the traditional old methods /products might give a more authentic and beautiful look vs modern concrete, and may actually be easier to work with. I learned lime plaster and lime based mortar to repair my sandstone foundation and parge the basement walls - it was a joy to work with - limeworks.us was very helpful source for these products.... incl. traditional lime based stucco. Adobe is a different animal though, my point is you want to start with the traditional approaches and then consider if the modern shortcut makes sense, it may or may not.