I had been to different eating outlets and my peeve is when customers do not return their trays and keep the table clean for the next person. I had eaten at McDonald’s, Mos Burgers and Subways to name some examples. It was a common sight to see customers walked away from the table after eating and left a mess behind.
When my daughter was young in the 90’s, eating at McDonald’s Queensway was a treat. To set an example for her, we would always clear our food tray in the disposal bin. Over time, it became ingrained and it was a natural thing to do. I cannot say that people are considerate nowadays.
I do not know why it is so difficult to return the food tray. Perhaps, it is the entitlement mentality: Since I am paying to eat here, the serving staff should clear it for me.