Its not a major concern yet, in many places. As noted in [TACO, 2012]:
"Concerns include…sprawl, in the case of early sparse AWES design configurations. Designs must use as little land and airspace as possible. "
http://www.energykitesystems.net/CoopIP/TetheredAviationConOps.html
Cellular Kite Networks, like kite festival trains and arches, aggregate large numbers of kites in close formations. Future AWES could achieve similar densities.