I would say if it's not hurting you then mind your own business.
You are probably wrong anyway. Maybe if your neighbour starts going through your trash in case there is something illegal there, even if he or she is not sure, then you can call it even..
- a friend living abroad & prone to the odd joint. Her dad came to visit & as he was leaving he wanted to take a cutting of her spamspamspam plant!! She managed to convince him it was tempermental & would last the journey.
- a family memebr had his dad come in & water his plants (including a couple of spamspamspam one) while he was on holiday. His dad used to be a Gardai.