It just sets my teeth on edge. I know the person sending it probably means well, and I am not entirely sure why it annoys me to be honest so I may well be being unreasonable.
I suspect it's partly because I am chronically ill so can't remember the last time I was "well".
But partly it just feels so unnecessary and not particularly professional (particularly when sent outside the organisation).
Anyway, I am partly hoping this thread will give me another perspective so I feel less irritated when I see it 
Ps yes I know it is totally trivial etc etc. I don't spend hours dwelling on it!