It’s good to always have a place to sit and a clean bathroom, not to mention areas I can work with my laptop and usually easy access to charging.
Snacks in the non-Flagship lounges are basic, but still decent. With the amount of flying I do, I would spend more money in a year getting (albeit) better food in the terminal, than on a Admirals Club membership.
On top of that, great quick customer service if things go awry.