Chiming in to add - Lasik!
I saved and saved to get mine in my early 20s, and assumed it's just the price you pay like anywhere else.
About 8 years later, went to same place for my wife and between age and experience I just said 'ah, sounds like too much we'll go elsewhere' and they nearly halved the price. Wish I knew that the first time!
However, don't overdo it. You're highly unlikely to get anywhere trying to negotiate at big box or grocery stores on typical items and likely just annoy the cashier. My brother used to get driven up the wall by people wasting time doing this - noting they were usually foreign people and that may have been how things worked in their native country.