Who writes the MLB Teams' Twitters?

Not sure how I got to this page but apparently the MLB Teams had a twitter sing-a-long yesterday to Taylor Swift's "Love Song." Of course in this case, it was "Glove Song."

I actually fully blame the Dodger twitter for steering the original MLB post in this direction.  

It is a funny read with some clever (and some lame) photos to go with the verses.  I am just interested to know who was writing it for each team and whether or not they had to Google the lyrics.  Then the question becomes, what made them feel compelled to join in if they needed to Google the lyrics?  Most likely it is a group of people working together to compose each tweet, but I like my little fantasy of some "manly" guy sitting in front of the computer, thinking of the perfect photo to add to the Taylor Swift sing-a-long....