Chess pieces. My first day playing the game, Tipper insisted on trading me this giant hideous "knight" chess piece in exchange for an hourglass. I put it up in Retail. Tipper bought it, gave it back to me. Then I gave it away to Mallary and two days later she sent me a present... IT WON'T GO AWAY.
Balloon furniture, kiddie set and gyroids. Especially Gyroids. Fun fact: they are literally called Haniwa - clay figures ritually buried with the dead - in the Japanese version, so you're digging up graves on a daily routine. Sweet dreams.
Even villagers describe those things as unsettling. really makes me wonder who put something like that in the game and why.