You guys are crazy trying to justify the price of these things.
Don't get it twisted, it's not affordability. It's principal. £35 to save you 5 minutes every now and then is not good value. In fact, you need both for it to even make sense. You still have to travel to either bank or sell if you have only one.
So £70 to save a bit of time. Insanity. ZOS still fall over laughing when someone buys one I bet.