[Quadcam]

I'm confused why people are wanting to lock the rear diff under normal driving conditions? This should be the last thing you want to do. What am I missing?

I expect they mean be able to lock the rear diff when in high (normal) range.

 

[Quadcam]

Having the rear locker has a few benefits.

Rear tires wear even, instead of the right rear tire showing the most wear. No I'm not talking about doing i wheel burn outs.

Having one also lessen the use of the front axle, less maintenance. Less tire cupping on the front tires.

Not turning all that extra drivetrain helps with fuel mileage.

You don't have the binding in the drivetrain when turning on to a dry patch of paved surface.

Thats a few, less maintenance, fuel, and tires are the main items.

Aren't you talking more about a conversion to Part-time 4wd than a rear diff lock?