In chiang rai last week saw something similar,maybe the bill was increased don,t know.But the customer little bit drunk and i believed he paid the bill but no fighting.Will he go back there i don,t know.I did see similar the next night too he paid and let it go.Next night he was elsewhere,drank else where and brought drinks for the owner all night jameson and soda.So that bar did well that night and the customer happy