Interesting thought experiment posed by a-bas-le-ciel:
1. Would you want to live in an exclusively vegan community?
2. If so, how much would you be willing sacrifice for it?
My answers:
1. No. Not yet, anyways. Only if the rest of the world is mostly vegan anyways (or at least a large surrounding region, like all of California or all of U.S.).
2. Nothing.
I would not want to live in such a community for various reasons:
First off, I don't want or need an echo chamber. I'd be restricting my opportunities to meet nonvegans who might be willing to go vegan if presented with adequate information. It's incredible how many rational & compassionate people are out there who aren't yet vegan because they lack the knowledge & confidence needed to make the change. I'd be restricting my ability to introduce nonvegans to the aspects of vegan lifestyles which I'm experienced with, like delicious vegan foods. I like to impress nonvegans with my sinfully-delicious creations; especially my lasagna**, burritos, falafel dinners, gingerbread cookies, apple-pie, and pecan-pie.
Secondly, this community involves sacrifices that aren't rewarding to me. An exclusively vegan grocery store might be more expensive in order to cater to a small group within society (would it? I'm not sure). If I want to shop for vegan food, I can easily get what I want from my nearby Trader Joe's and local produce store. Just because they sell nonvegan food too, doesn't make it hard to find what I want. Shops don't deserve any moral blame for selling nonvegan foods, because for shops to go vegan would not reduce total demand for such products. Consumers have the responsibility to avoid animal-derived foods.
Everyone: I highly recommend subscribing to a-bas-le-ciel!
* https://www.youtube.com/watch?v=3qibyKm7Y9c
**I follow the VBMC's recipe ( https://www.youtube.com/watch?v=JZns7LYIpsw ), with some slight modifications. I like to break apart blocks of extra-firm tofu (I use 198 grams total) into tiny pieces such that they becomes a clumpy paste resembling ricotta cheese. I then mix it into the tahini sauce in each layer. I sometimes create alternating layers of tahini sauce and muhammara. It's even better that way!

The VBMC encourages his viewers to be adventurous and use what ingredients they like. Here's what I use:
-9 large lasagna noodles
-1 finely chopped onion
-2 bell peppers of different colors
-Lots of mushrooms (white and/or brown)
-About 1lb (0.4536 kg) of spinach
-1 large jar of TJ's tomato basil marinara sauce
-Tahini sauce and/or muhammara (preferably some of both)
-1 tsp of chili powder
-0.125 tsp of cayenne powder