I watch QVC when they are selling Charlie Bears and occasionally look at IdealWorld's technology shows, but otherwise I don't bother. My mum watches QVC all the time though, whether it is for jewellery, bedding, clothing, gardening or make-up. A lot of the time we use it as a guide and then buy from somewhere else.
When my baby was little, and I was feeding in the night, I'd turn on the tv and if I didn't have the remote nearby once I'd sat down to feed, I'd watch it. I'd get kind of hypnotised and by the end of the 20 minutes, I'd be thinking "that would be great that....(insert gadget we would never use)" so I'm assuming that's how it works, it wears you down til you think it looks fabulous. I never did buy anything tho
I have occassionally switched over to the shopping channels but haven't been inspired enough to purchase anything. I figure you can buy similar products at the discount stores anyway and you can see the quality of the product upfront.