It was well known that Gandalf was 'hiding up in the Bag End.'

[Aerindis]

I wanted to add some thoughts on the disparity between Gandalf's notoriety among the hobbits and their personal acquaintance with him, but this is all I can think of:

 

[Ambrosius Aurelianus]

Haha, I can empathize. For some actual thoughts to add: well, Gandalf's nature as a wanderer and a wizard naturally shocks hobbit sensibilities, making him an easy subject of gossip, especially since he won't just pass through or stay away, but stays *in* and influences otherwise upstanding hobbits to scandalous adventuring! On the other hand, those who actually get to know him always like and trust him.