22 Feb 2015 11 Mar 2015
This might be glitched for those who already completed this achievement on 360 and then transferred their profile to Xbox One.
I'm in this category, and so on Xbox One all 20 stores have the green check mark to say I've robbed them already. The achievement didn't pop when I launched GTA Online (like some others did) so I went around the map and did them all again.
I did this three times - all 20 stores - and still no achievement. And no percentage progress for it either.
To get this achievement to pop, I created a new online character (thus clearing the map) and was able to earn the achievement by robbing all stores again. To make it faster, I didn't bother running from the cops.
Hold up store, get the money, wait for the cops or store owner to kill you, respawn, go to next store.