More than the church not having anything nice to say about him (thief!), these notes place him in a certain area and the fact that notes would survive this long is simply amazing.
http://www.washingtontimes.com/news/2009/mar/15/medieval-note-casts-doubt-on-robin-hood-lore/
It is good to know that it does give credence to the existence of a historical Robin Hood, and his base of operations.
Historically we have had a habit of romanticizing outlaws and rebels, even in modern times. Robin is probably no exception to that rule. ;)
Don't forget that the church in those times had most of the money and power, so no wonder they didn't like someone who stole from them and gave to the poor as it made them look like an uncaring, unloving institution which it some areas it was.