One bit of realism that is thankfully missing from video games is the natural wear-and-tear on your looks. If you're actually running through a secret underground bunker shooting Soviets/aliens/zombies, your hair is probably not going to be perfect. But in videogames, Cloud's coif is always impeccable, James Bond's tuxedo is never wrinkled, and Link doesn't have to go on any fetch quests to get braces.
Now imagine that you didn't have to keep up your appearance in real life, either. No matter what you ate, your teeth would always be flawlessly straight and white. You'd save so much money on haircuts, because your hair wouldn't grow unless you went to your customization mirror and told it to. There'd be no acne, no "back-ne," no bad hair days, and your clothes would always look perfect. Being a teenager would be so much less awkward.
In video games, we have access to the most sought after prize in all of humanity's storied history: the mulligan. As long as the game is saved in an opportune spot, you can fight the boss over and over again until you get it right. Die? No problem, reset from the save point. Accidentally drop an important item? Just reset. It's like Groundhog Day, but actually helpful.
If save points existed in real life, chances are they'd be used for personal gain, like acing a test, or saving right before having sex and then just having sex over and over again. But the real potential lies in the science and medical fields. If researchers could save, test out a new drug or procedure to figure out its flaws, then reset to try again, we'd have cancer cured in relatively no time. Really, the only downside is that seeing Mr. Resetti all the time would totally be a buzzkill.