Let's say you have enough to live on at 62 or 67, and are still in good health. And that taking SS at 67 would give you an extra $21k in annual income (before taxes), or at age 67, $30k in extra annual income. You don't need it, but you could certainly use it for travel. Once you've reached the FRA, your spouse qualifies for maximum spousal benefits. Why not take it then, given the chances that you 1) won't live to 100, or even 90; 2) SS benefits could be reduced in the future; and most importantly, 3) you may not have the health, stamina, or desire to travel or need the extra money after 70 to 75?
If you're leaning towards a lean retirement, taking SS at 62 might also allow one to have many fewer years to bridge the spending gap between 4% SWR and the cash infusion from SS. Some don't have any heirs to leave assets to, and some want to maximize this. Everyone's situation is a little different.
Taking SS early allows you to keep your retirent accounts invested longer (which may help with longevity and long term care risks), and still spend more money in travel, dining out/toys. Whether this makes any sense depends on your assets, allocation, etc.
It's not always about how to maximize benefits. For some, it's about how to maximize the quality of your life while you have the will and health to spend. After my mom turned 79, she stopped driving, did minimal shopping, and her spending plummeted. She was banking money every month with a very modest income.