By now most of us have heard the urban legends of Smurfs vs. JW's.
Such as smurf dolls walking down Kingdom Hall aisles or strangling JW babies (replaced dingos eating them in Australia LOL).
the initial problem JW's had with Smurfs was that on the TV show they were conjuring up spells, later more ummm "enlightened" JW viewers started questioning a community of all males with only one female (smurfette).
So JW's felt that it was not appropriate for JW children to watch shows about magic.
It is this same reasoning that has scared some away more recently rom Harry Potter novels and Pokemon.
It was stupid when it involved Smurfs and is just as stupid now.
But there ya have it, the main reasons (if you can call them that...) that JW's hate Smurfs and developed such wild stories to enforce their opinion.
Kismet