So Safeway got acquired by Albertson's a few years back. In August, this store removed the Self Checkout lines. Looking at news stories and press releases, Albertson's decided to remove the Self Checkout lines from all their stores back in 2011. So from these two facts, I'm guessing the reason for the self checkout removal can be tracked back to Albertson's management.
There is a reason why the Albertson's at Tatum and Greenway closed after the Safeway merger instead of the Safeway across the street. There was never anybody in it. Albertson's pretty much isn't competitive in the ultra competitive Phoenix grocery market.
So after the removal of the self checkout lines, I'm now a bit annoyed at this store. I severely dislike Fry's but for items that Fry's can provide, I'm heading there. They still have self checkout lines. The new express lines are so much slower than the previous self checkout lines. After using self checkout lines at Safeway, Home Depot, Lowe's, Fry's and Bashas' over the last ten years, I've become pretty quick at using them.
So Safeway/Albertson's management. Re-think your strategy and get out of your bubble. For reference, I'm one of those customers who rarely spend over $30 each shopping trip but I earn multiple gas rewards on a monthly basis.