Kristen’s comment > Likes and Comments

That's what I thought. In the 1st book I figured there were other cities like themselves

Not that they except canned foods from the mysterious imaginary farms on the other side of the world

Thinking back, I think I do remember her saying something about having farms outside the city.
Of course, I think some of Amity's land is outside the fence. So who really knows?
Maybe in her little Abnegation world she considered "far away" to be Amity.
With first person narrative descriptions are always influenced by that person's perspective.
I think she visited Amity once as a child, and to a kid, a ten minute car ride can seem endless. So maybe she was thinking in those terms.

Although, I don't remember Amity having any sort of live stock, so probably they just assumed there were people outside who just did that, and didn't think much else about them.
She never gave much thought to who drove the trains until later either, but she knew someone must be doing it.