Is it bad that my childs Daycare teachers often greet him in the morning

[Shnazzypants]

with,"hello grumpy?"? This has happened numerous time. And it really upsets me. I recently wrote to the centre about it. However a teacher I spoke to prior to the letter said that it was just lighthearted and shouldn't be taken seriously. She said I shouldn't be upset about it at all. I feel like my child is being labelled and would have thought that this was not a positive way to greet a child even if it is said in a high pitched happy voice. What do you think? Note: He does sometimes arrive in a mood that would appear grumpy but I think it's just that he is shy not grumpy and he quickly settles in fine.