Did you ever wonder why 'easy open' features never work? I have. And they are not a convenience designed only for human consumption. Have you ever tried to pull that little string at the top of a feed sack? What about that little pull feature on the package of Peanuts? You know, the one that either won't 'pull' or pulls half way and stops? Yeah, that's the one.
So here is a little food for thought: "The organization controlling the material equipment of our everyday life is such that what in itself would enable us to construct it richly, plunges us instead into a poverty of abundance, making alienation all the more intolerable as each convenience promises liberation and turns out to be only one more burden. We are condemned to slavery to the means of liberation." - Raoul Vaneigem. Which is just a long winded way of saying what the old proverb says - 'Every convenience brings its own inconveniences along with it.'
Besides, in my estimation, if they worked, well, that would just be way too easy,wouldn't it?