You have illustrated the question yourself. At a picnic, you drink out of plastic by necessity, and in such an informal situation you would be far more likely to nip a Jim Beam than a Speyburn 35. At home, you would never choose to use plastic. It's not appropriate to your purpose. The situation being described is a matter of taking the appropriate choice away from persons attempting to enjoy a fine dram in public accommodations. If I have to drink a Cadenheads Clynelish out of plastic at the Bow Bar in October, I'm going to be a bit upset. If that is indeed how it's going to be, the point could be made that it will hurt exactly that segment of the trade that has nothing to do with the type of problems being described.
I'm not going to comment any further on this until I have actually read the article (

) and perhaps done a little more research on the subject. There is a tendency sometimes for us to let speculation and rumor run away with us, and the next thing you know, we are talking about Bruichladdich's column still or such. The only thing I will add is that I wonder whether there might be plasticware that we would find an acceptable alternative to glass; the image we have when plastic is mentioned is of disposable beer cups and thimbles. The notion of plastic, after all, is pretty...plastic.