"They way they envied us from across the dinner table that first night in R, staring at us, the young, the old, men, women - every single one of them at that dinner table - gaping at us, because we were so happy."
Oliver reminiscing in Elio's presence -pg 238 Call me by your name -
Le Petit Poucet left pebbles behind him so he wouldn't lose his way home and Tim hid the pistachio shells in Armie's couch so he would remember him every time he found one. At least that's my interpretation. Maybe we'll find out one day...