Sometimes they are standard letters. I work in the department I needed an appointment for, got a referral from my GP and very cheekily got one of the girls in appointments to find me a soonest free slot. When she looked one of her colleagues had made me an appointment 6 weeks later than the one she found for me. So she cancelled that one and made me the sooner one. I told her not to worry about the letter. I got my original appointment letter with 4 sheets of wasted paper on top of the one I needed for the appointment, it was then followed by another the following day saying much the same as yours about the cancellation, rather than sorry you couldn't make your planned appointment and another the following day giving me all the new details with the additional 4 sheets of info appear. what a waste!
I am sure people wonder where their NI and NHS taxes go......