Hmm. Taking out that much material would really weaken the structure for handles.
edit:
Nevermind. You're right it's for the handles. They screw in on the perimeter of the cut-out - so no issue with weakening the table. Very cool handles by the way.
Yea, see:
I kinda like the look of these, so don't mind the 15min with the router to recess them. The set is from Amazon for ~$20 iirc