I try to be as low waste a person as possible. Using these custom fit liners ensures I'm not taking the trash out before the bag is actually full (like when you use regular liners in your garbage can). It's also nice to have the option to buy the liners in different quantities to suit your needs. I really only need to buy liners once a year when I purchase the 60 pack. I don't think I'll ever purchase any other brand than simplehuman!