I asked a summoner to use LB the other day in Wander's Palace to kill the big pull before the last boss, after not using it and we kill the group he explained that he didn't have room for it on his action bar. I felt bad for him, told him how to get more action bars and he said he knew, but played with a controller and doesn't want to swap bars, so he just loads 8 skills/macros on the first set and only uses those.