Although it's an easy way for you guys to make money, yes.
This has no relation to the fact that the we get to test the new-gun content on the Test Servers, right? With the Flash Sale Promotion helping flourish the Test Server community by a larger amount due to the Flash Sale. Giving you guys a much larger group of people buying Energy, allowing for a much larger group of players to test any new content coming at us than before.
Or am I just reading into things too much and you just randomly did it for no apparent reason?
I feel like it was a good move for Three Rings in general. Without paid elevators, they need to find a way to have us spend money on their game, plus we all get excited about this new sale, and focus shifts away from what they've messed up on and are (hopefully) fixing so that they can work in a less pushy atmosphere.
But I do hope this means we'll be seeing more content coming our way sooner. Money is an amazing motivational object.