In sales/economics the term is upsell, not uplift. The Aschen plan is basically the plot of V, aliens arrive, advance our technology, and then try to eat us, or use up our resources. It makes total sense for a hikineet species, they stay on their world, a few of the adventurous types (or descendants of a conquered people) venture out in search of planets, and you take over the occupied ones, since you know they are safe, there won't be any strange virus that scours the land every hundred years, or underground vampire bugs. As for whether or not an advanced people would be content to wallow on a primitive planet, these are the ones that didn't ascend when the chance was given, they chose to come back to Earth, these were probably already the Amish among the Atlanteans. Plus, they probably looked back at their history, and decided that technology just keeps leading them to the same end.