LOL, yes, from the shelf. If I'm in an obj context, I almost always use the tab menu, though, creating a box or alike, but if I'm in the scene context, I often use ctrl-click on the shelf to create spheres, boxes, etc…
And checking now, it's not about ctrl-clicking, in H15 you get “teleported” (Jeff Wagner's phrasing) into the obj context creating any new object - in H15.5 you stay in scene context.
Unless this is something I somehow ticked on in the H15 settings, which might be the case - if so, I just want to know how to get it back on.