Tooth paste tubes (or any other product contained in a tube)
Same size, same weight, higher prize and larger hole so that the product is consumed faster and hence must be bought more often.
"Destruction chips" contained in electronic products so that you have to buy new ones. Like the chip in (especially) laser printer toner cartridges so that they only last a year, regardless on how much toner has been used, then go "empty".
Money, they used to last longer a couple of decades ago
