If I understand the ebay description - the cut binding is 1.15 per yd. There is a chart indicating the number of yds needed for each size quilt. For a double or queen it is about 14 yds. and that is about 8 strips at 40" wide or 20 inches of fabric. If fabric is $9 per yd, then that is about 3/4 yd or $6 or so.
Now If I calculate correct. the equivalent of a yard of the cut binding is $16.56. Big difference.
Less expensive to learn to cut your own.