I feel like Fate Accelerated Edition shouldn't cost so little. Does anybody know why or were the developers just being nice?
Economies of scale.
We printed like 13,000 copies of those. Because we hit that economy of scale, our actual cost (not counting up front costs of writing — minimal — and art — reasonable) came in at less than 40 cents per copy (close to 35). To make a MSRP $5, 40-page book work for distribution our costs needed to be neatly under $2 per copy, so that's given us a lot of breathing room. It also means that those 13k copies cost us maybe $5,000 to print. And, yeah: the KS presold enough copies of FAE to more than cover that.
So, they made a decent amount of profit at $5, and why charge more if you don't really have to, particularly since it's their introductory product?
It's part of their marketing strategy. FAE is a simpler version of Fate; if you want something with a little more detail, you'll want to buy one of Evil Hat's other Fate-based products. "If this little taste interested you, why not buy one of our other products?"
The other advantage of having a low-cost entry point for the Fate system is that it leads to more people playing Fate. If you and your friends enjoy FAE, then you'll tell other people about how much you like FAE, which will lead to more sales of various Fate-related items. And having a low-cost product means that you'll sell things to those people who wouldn't pay $10 for an unknown RPG product, but might be willing to drop $5 on something new.
From Fate Core and Fate Accelerated are not different games by Fred Hicks.
FAE will also catch enthusiasm because of its price point (you can buy enough books for your whole table for the amount you’d normally pay for one player’s handbook in another system) and because — frankly — it appeals to the lazy as well as the young/new player set. Lots of folks don’t have the time to game that they used to, and FAE’s going to look particularly shiny and sparkly to those folks. Myself included. This also means it’ll catch a certain amount of fire for folks looking to make a convention slot happen with no or little prep.
So from the perspective of ease of entry, a lighter and less expensive book hits a lot of the high points of their marketing strategy for Fate Core as an platform, not a game.