A flat-bottomed bag is formed from a flexible sheet that initially is flat prior to being manipulated to form the bag. The sheet is a laminate of a first web and a second web laminated together by an adhesive layer disposed between the webs. The sheet defines a plurality of serially connected side wall panels collectively defining a vertically extending side wall of the bag, and a plurality of bottom panels respectively connected to the side wall panels at respective fold lines. The bottom panels are folded about the fold lines and are attached together to form a flat bottom wall configured to support the bag in an upright orientation. The adhesive layer is in a partial-coverage pattern that includes adhesive-free regions located along each fold line between each bottom panel and the respective side wall panel connected therewith.