GS makes the phone call for for you.
Strange town broken down on the side of the road and most likely don't even know what towns you are close to and no big fat yellow book to look one up, if you even know what town to look in. IMHO I am happy to have and call GS and let them find one for me.
I can't believe the posts that people think that by having GS ERS entitles them to INSTANT tow truck arrival. Like they have them sitting in the wings all lined up just waiting for 'them' to break down and be there in seconds flat.
Tow companies can give you an arrival time and what if the previous breakdown call takes longer? What do you want them to do? Drop that customer and run to you?
As long as I have been using tow companies with or without GS there are a TON of variables on how and when they can get to you.