Seems like this qualifies as a bug, especially since the similar 'objects pointing to this value' works on any variable selected in the inspector. Ought to be fixable, I'd think.
This might be harder than you think - I remember briefly looking at this problem way, way back when I first encountered it and not being able to come up with a good solution - the issue is that you do NOT want to include the inspector in the reference chain to the object and that is not exactly trivial to do. But if you can find a way I'll be forever grateful ;-)
Cheers, - Andreas