The initial idea was how to harness consistent and powerful high altitude wind. Sky Windpower (https://skywindpower.com/) has built one of the first prototypes. The purpose was harnessing high level jet streams. Then, for some AWE companies, the tethers were shortening, the purpose being harnessing low level jet streams (LLJ), then yet below. In some way the main purpose became different: using less material, then a nomadic device, that due to difficulties by using long tethers (land and space use, drag, weight…).
Kiwee is a simple (not crosswind) and efficient small device on the market, flying at a high elevation angle. It does not reach LLJ but an altitude that can be seen as high in regard to its size and to competing ground turbines, so the advantage of harnessing more consistent and powerful winds also applies.
Things are a little different with some torque based and crosswind kite devices, all flying with a low elevation angle (30-35°): the expecting benefit may be limited to the use of nomadic and light equipment. But the advantage can be significant in regard to an expected high power, and a possible use onshore and offshore.
Torque-based turbines like SuperTurbine ™ or @someAWE_cb’s, or comprising TRPT like Daisy or perhaps rotating reel, could be improved (electronics and other) then marketed as low altitude (below 50 m) devices.
Crosswind kites (@Kitepower, @katieschaef, @tallakt’s Kitemill…) could also be marketed before reaching high altitude winds for the same purpose as previously indicated, by using a short tether of only 100 m. In the same time the proportions between the tether length and the swept area would be more harmonious, knowing a kite in the end of 1 km tether should be quite huge to produce enough power to compensate the high space use.
To resume, there are some possible markets for AWES now, but not yet for the absolute high altitude winds.