Info Control Bar too long

[badgersurfer]

I was trying to add the Placeholder icon to my infobar and couldn't. So I pressume you can only add icons to the relevant bar. When I dragged and dropped it it finished up as a toolbar of it's own with feather next to it.
The problem I have is that the Info Bar has as much black space as icons. Normally toolbar autocrop themselves to the end of the icon rack. Is there any way of removing the black space or can I create a custom bar with just the icons I need?