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I can see where it would be done for a corporate team gift, or for personalization, or for a corporation to put their logo on it for instant ownership identification.

This place does it too, I've used them for invisishields for years: http://FusionOfIdeas.com.
 
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Would anybody on here get it done but still use their case to prevent it from getting scratched?

I would
 
My workplace has this type of laser engraving system. I use it all the time to zap my name and number into personal items such as chargers and pens.

No reason to do it to my phone though.
 
Can you back that claim up?

Claim? Where did I make a claim? I voiced--typed--my opinion. It's like saying [enter car company name here] would deny warranty service to your engine because you got a custom paint job.
 
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