I just can't get the watering can in my current game no matter what! I got it in my other game after buying more plants from the vendor, but no plant vendor yet in this one, only the stupid fortune teller, art dealer, and housewares salesman. Twice each! Grrr.
Does anyone know if buying the butterfly crossing sign makes you have more butterflies? Does the spider sign make more spiders? Does the water sign, I don't know, make it rain more, maybe? Or are they all just decorative? It would be cool if they had a purpose.

Tyger- I have the same question! Do any of the town features impact the game? Other than the beauty level....

I don't think so; they're just decoration. They will add a little to the beauty level, but no more.