It isn’t a matter of whether we think it is rude. The issue is whether it is rude.
If I were a former business partner of your father, is it rude for me to enter your house and tell awful but “what I say is truthful” tales of your father, tales that you had never before heard?
And is it a crime for you to have let the community know that you think your father was a great guy?
Putting a poster in a bus or subway station isn’t “Entering your house.” If they put it in a church, THAT would be rude.