That's been an option on many cars for 20+ years (the Omega did it), its to allow ventilation of the car prior to getting in for hot climates (and the rare hot days in the UK), very useful. 
Yes, great for letting some heat out as you walk up to a car. Also, handy if you leave a window down and get out of the car as holding down the lock button will usually cause all the windows to go up. 
I can see the point of closing them on the button, but in 60 odd years of motoring in UK, there may have been 2 or 3 times when I may have wished to open the windows remotely instead of unlocking normally and opening windows. I do recall a time in Africa where it would have been useful, but in the UK? Nah!
Its a feature I regularly use in the summer 
But when? I suppose
if your car is securely parked at home or elsewhere during the heat of a rare English summer day,
and nothing of value is inside,
and you are happy to wait with the car in view, it might be useful. Any other time, opening the door will do. I honestly can’t think I will ever need to use it in the UK, other than to demonstrate its availability. Not accounting for climate change obviously. How many OOFers know - or knew - it worked on the Omega, and used it?
I have switched it off in the in car menu, as the danger of the windows accidentally opening, and possibly flooding the inside of the car, as nearly happened in my case, far outweighs the extremely rare requirement to open them remotely.
