Yes, I heard of a man in Milton Keynes who bought 5 TVs during the night at Tesco. No discount, no material thing is worth the undignified behaviour of some of the "people" I saw on the news.
I avoid these types of sales after an experience I had some years ago. It was around the time that Woolies was closing down. I popped in one morning because I needed a frying pan and was shocked to see the hordes of people with blank faces, on the hunt for hugely discounted items. I reached out for a frying pan on the top of a stack of about 8 and at the same time a woman grabbed the whole stack. "Mine!" She snarled at me.
I kept hold of the top frying pan and said politely "yes, but this one is mine". There then ensued a bizarre 30 seconds where this woman tried to wrestle the frying pan from me, and I could not believe my eyes when she lowered her head, bared her teeth and went to bite my hand!!!
I shoved the frying pan at her, and said "here you go, you obviously need this frying pan much more than I do," and left the store, but afterwards, I felt really shaken and tearful that something like this could happen.