I just realised that these icons probably are placed best at the Target segment pane:
Since they are being used there (debate about the flag possible)
Whereas these ones:
Are referring to the Source segment pane (you make the selection there, then click one of these icons).
Well, actually the decision to place those icons where they are now was based on the frequency of the workflow/navigation actions. Those icons closer to the target segment are the ones which are used more often than the others. You can move the source segment toolbar closer to the target segment as well (menu View > Toolbars > Reverse source segment toolbar).