My local grocery store replaced about half the human checkout lanes with 3-per-lane self-checkout, and about 90% of the time I go shopping I don't have any line

My local grocery store replaced about half the human checkout lanes with 3-per-lane self-checkout, and about 90% of the time I go shopping I don't have any line to wait for. The problem arises when they try to do a 1:1 (or nearly so) replacement.