Should a entire bathroom circuit run from a GFCI outlet
That very typically happens when Goober wires it. (I don't know who Goober's Canadian cousin is, maybe Joe Gongshow?) 

Joe hooks it up, and goes "hey, what do I do with these extra wires?  Oh look, 2 more screws under this warning tape I did not read". 

Things should only be put on the LOAD screws if you really want to provide GFCI protection to them.  Otherwise, the LINE screws usually are able to accept 2 wires via screw-and-clamp.  

Lights and fans do not need to be on GFCI unless they are inside the shower.