Whenever you buy anything in Taiwan and are given a receipt, you may receive a physical printed out QR ticket along with your receipt. If you are a resident, you have the opportunity to not take a physical printout but instead have it added digitally to your collection. These are entries to a government lottery that was started to incentivize reporting sales and therefore allow the government to collect more of the sales tax owed to them.
These QR lottery entries are done as a straight entry into the lottery, not a multiplier. It has led to silly situations such as the one where a person would, for example, buy 500 plastic bags for NT$1 each in 500 transactions every day and profit by winning sums in the lottery. (My understanding is that the sums one can win start at NT$200, but I am not very sure.) This sort of gaming-the-system is looked down upon by the government and I believe one of these enterprising people were prosecuted.
Every time I visit Taiwan, one of my relatives will ask (or demand) all of my receipts. What they really want are these QR /fah piao/ codes that are entries to the receipt lottery.
