What is the obsession with heat insulating glass

[Deleted member 11979]

Reading the adverts written by some of the sellers specialising in Mercedes from the 80's and 90's, a lot of them make a point of listing heat insulating glass as a feature.

Is this actually anything other than standard car window glass slightly tinted green? Was it actually an option on any of these cars, or part of the standard specification?

 

[renault12ts]

I have blue heat insulating glass as standard...as anyone with an AG does. When selling a car you mention everything...it sounds good doesn't it. But I have no idea what difference it makes.

My mothers 1997 W202 also has insulating glass listed.