I was faced with cutting hand-holds in a number of boxes.  While the typical approach is to drill two holes and connect them with a jig saw, I never had much luck with that and dreaded the task of drilling, sawing, sanding and routing 72 holes.

 

I used a jig similar to ones I've used before.   I simply cut a strip out of a piece of 1/2"plywood that determined the height of the hand-hold.   Then I glued the plywood back together to create  the width I wanted.  I added a stop to set the distance between the top of the box and the top of the hand-hold.

 

Since the boxes were of a couple of different widths and I must use it again in the future, I did not put a stop on the other side, but simply marked the center line of the box and lined it up with the center line of the jig and clamped in place.

 

Then using a plunge router with a bushing and mortising bit routed out what amounts to a large through mortise.  Use a roundover bit on inside and outside of hand-hold   You could also use a top-piloted bearing bit if you wish.  

 

I don't mind the square-ish ends, but if you prefer the more traditional rounded ends, just round over the inserts before you glue them back up.

 

old Normie used a similar technique to create hinge mortises.

That'll work nicely.  Looks good too.

I did something similar but made the hand holes extremely rounded like a hand saw handle . Did a pattern and uses a pattern bit in router to cut then round over as you did. Thought I had a pic but cannot find one.

Speaking of Norm, and sorta of what @Gerald said-

 

These hand holds are comfortable and are created with a jig like you did.

 

I made a couple of these butler tables. The hinges cost more than the wood. The first table was solid Pennsylvania walnut and was a gift to my brother. They sold it at a yard sale 

72???  Hmmm  I've heard that number used elsewhere.

Anyway  why not just line 'em up and  pound a  few 30-6 rounds through 'em.