Why do cats lick plastic?

I have a 2 year old Himalayan Cat named Felix. He will be 3 in April. He drives me crazy because he licks plastic bags. I can hide them keep them put away chase him away by clapping hands and usually saying Felix! get away from there! but he literally goes HUNTING for plastic bags. He chews on them and eats them, he just won't stop and I'm absolutely petrified that he's going to get into a plastic bag when I'm at work one day and I'll come home to no more Felix. He will go into the kitchen and open the door under the sink JUST to chew and eat the plastic bag thats in the garbage. I don't understand it because its not like he's hungry because I ALWAYS make it my top priority to make sure he has fresh food and water. I've tried everything, and I don't know what else to do... I'm so scared I'm going to lose him because he's eaten plastic from a plastic bag. We can't even put up our Christmas tree this year or put our presents out because he will eat them. He won't stop. I love him to death and pieces and I don't want to lose him or see him sick. I can't stop him from hunting for plastic bags. I don't know what else to do. I'm at the end of my road. I'm just so scared... I love him so much. He's like my own child. and I want the best for him. please help...
thanks