That's a great question that touches on a very practical, if slightly unusual, concern. The core goal is to place the bag in the bin in a way that makes it difficult, unappealing, or time-consuming for someone else to retrieve it. Here are some natural, discreet methods people use.
First, if possible, conceal the bag within other waste. Don't just drop it on top. Look for a bin with existing trash, push aside the top layer, and tuck your bag underneath or in the middle. Burying it under coffee cups, food wrappers, or newspapers is very effective.
For very deep bins, consider adding weight. If you have a partially finished drink (like a soda or coffee), you can carefully place it inside the bag before lowering it. The liquid weight helps it sink to the bottom and makes the contents unappealing. A few pieces of litter from around the bin (like stones or more trash) added on top inside the bag can also work.
The placement technique matters. Lower the bag slowly by its handles to the very bottom of the bin. If the bag has ties, secure them. Once at the bottom, give the bag a slight twist or tuck it against a corner before releasing the handles. This helps it settle in a less accessible position.
Finally, timing and discretion are key. Choose a moment when the area is less crowded. A quick, smooth motion appears more natural than a hesitant one. The idea is to make the action look like normal disposal, not a deliberate act of securing something.
Remember, public bins are just that—public. For absolute security, the best method is proper disposal at home or in a private, secure location. But if you must use a deep public bin, these steps will make your bag far less likely to be targeted.