Glut of Syntec 5W-50

Athens, Georgia
There are cases and cases of Syntec 5W-50 in nearly every auto parts store in town here. AZ is the only place that carries the full Syntec line here, including GC, but they still have more 5W-50 than anything else. O'Reilly's doesn't have 5W-20 or 5W-40 (which one would think to be better sellers), nor does Napa, nor does Claw-Mart, but all have tons of 5W-50. AA does not carry 5W-40 here, but has tons of 5W-50. Is the Syntec 5W-50 a particularly popular oil? I would have thought its usefulness to be somewhat restricted. [I dont know] Has anyone anywhere else noticed this? Or is Castrol trying to dump its excess 5W-50 on a poor, unsuspecting town of cafe intellectuals, addle-headed grad students, and wannabe rock stars? [LOL!]