Can we already get too much "on demand"?

Tom just had a call from BT, trying to sell him BT Vision - their TV service where you buy a box for £15 and then for a small amount a month (the prices all sounded OK to be honest) you can get lots of channels, and as well the ability to record live TV (Sky+ equivalent). The bit that sounded the most interesting was the fact that you can browse old TV programmes (and I think films) in the way you can on Five.tv and 4OnDemand. Which is great if you miss something! And you need never buy another box set again! But is it spoiling us, having too much on demand? Is it just adding to a culture where we expect to have everything at our finger tips? Isn't it nice to - whilst not basing your life around TV - know that there's a certain night of the week that your favourite show is on? And won't it detract from how it can feel to chill out on evenings or weekends watching old DVDs and Box Sets? Tom's example was that he loves chocolate like he loves some comedy series'.... but if he had a chocolate bar every day whenever he wanted, would it still be as nice? Would it taste as good if it wasn't a treat? Would be interested to hear your comments on this one - is the future one of convenience, or is a little bit of "saving for best" not always going to be nice?