Haha let's just be happy :P I think it can be annoying, and seen as spam depending on how you look at it. It's obviously understandable to think many people will get annoyed..

I for one, decided to make it a fun thing when he posted 'I am Groot' on my latest post, and decided to reply saying the same thing :P

Unlike @ionlysaymeep, this idea actually makes sense if you think about it haha.. Groot literally only says those three words in 'Guardians Of The Galaxy', and everyone knows Groot lol!

Just my opinion, but I have decided to rather look at the fun :) He isn't doing that much harm.. I don't see him really spamming as such.. But I will think differently if he literally starts to bombard people..

Cheers! :)