I worked with a guy that did a couple of tours in Nam. He said when they went out through the villages the locals would beg for cigarettes. If he threw out some Winstons or 'Boros they'd yell GI number 1, GI number 1! When he'd throw out the cartons of Pall Mall's (no filter of course so nobody wanted to smoke them) they'd yell GI number 10!!, GI number 10!!
That is true, they loved the menthols, especially Salems.