I agree that there are a number of secure ways to fix a frame to a wall, rather than only hanging by wire and hook(s).
Look into your suppliers hanging hardware listings.
Or, most hardware stores carry a few options.
Or, look into one of the Grumble sponsors...
https://888mfgcorp.com 888 Manufacturing Corporation - Powered by Network Solutions.
Does your customer know the difference between Anti-glare/Anti-reflection coatings and Reflection Control surface glass or acrylic?
Both could be considered "non-glare", but are very different. Both in appearance and cost.
I have one client who insists on Reflection Control Conservation Acrylic for everything I frame for him.
Even when he brings ready-made frames for custom matting, he'll have me change the production glass to RCC Acrylic.
When I asked him why, he gave me two reasons.
1-He prefers the"old fashioned" frosted appearance of Reflection Control.
2-He feels safer with acrylic in the event of an earthquake. He has a lot of frames on his walls.
Fair enough. He asks for it, so I do it.