I had the exact same problem on my Ranch Kettle. I bought it brand new and discovered a chip in the exact same spot - right where the hole for the handle bolt goes. I never realized it was damaged until I took the handle off one day so I could put vintage wood handles on in place of the plastic ones. I called Weber and they sent out a new lid. The new lid developed the same problem, Weber sent out a second new lid. The second new lid developed the same problem, Weber sent out a third new lid. The third lid developed the same problem, Weber sent out a FOURTH new lid and a special set of washers to go between the handle and the strap. That's what was causing the problem.
I had the first model year (2012) for the new redesigned handles with the higher profile. Apparently, when I was lifting the heavy lid, the strap was placing stress on the enamel right at the hole, causing it to chip and break at that particular spot. The spot was down to bare metal and I feared it would start rusting. I bought the grill brand new as I do with all my Webers and considering the fact I paid full revenue for it, I wanted it right ...and Weber made it right.
Keep in mind, these are lids for a Ranch Kettle, not a 22.5. Each lid had to be delivered by a freight truck - not cheap. That is exactly why I buy and support Weber products.