When you don't have to work and you can spend the time. Businesses completely discriminate against you for wanting a good or service at different times. Look at matinee movies. If you want to go to a movie at a non-peak time you save money. Go when it's busy and pay more!
Happy hour? Early bird specials? Being retired or the flexibility of time can save you money! This is something to think or consider as you retire. However, don't assume that you will be doing less because you often do more.
When you can do what you want when you want it's way way cheaper!