Initially adhesives were used in auto body manufacturing to overcome an issue or weak spot in the construction of a car. As time has gone on auto body glue has become more and more beneficial. First the skill required to apply the adhesives is much lower as long as you can properly follow the mixing and application guidelines. Also glues are lighter weight and can join dissimilar metals like aluminum body skins to a steel inner structure. When used in modern automotive assembly the glues may be baked over an extended period of time to fully cure the joints without distorting the metal.