CMIIW, In my opinion its more like buying an experience of using acronym rather than your average uniqlo or whatever brand that can really accommodate the necessary functions that a normal rain jacket or pants can.
You dont really need the extra acr funtions like the forcelock, grav pocks, etc as mentioned above.
It is not necessary, it really is not but some people found the features to be very useful so each piece resonates differently with every people.
Some use grav pockets to store their ski pass or train passes, some use their escape zip since it would be easier to unzip if one of your hands are dirty or occupied with something else.
Sometimes its just a matter of enjoying the designs that the designer meant for the item.
However, the design has to work on its own, regardless of how useless/useful it is to the user.
I myself have a background in architecture and i will always remember what my professor told me : “if there are no problems to solve in design, create your own problems to solve.”
So i think sometimes acronym does the latter.
Besides, acr wouldnt be as much fun and cool if these features do not exist right?