During surgery I can kinda get, but after, it's better to just stay active and get up and around. Even the flying thing is bogus unless you're a business man taking several flights a week.
It's just a major inconvenience for anyone to bother with after surgery when walking is better for you. It's also something you can't put on yourself after surgery as you're more likely to injure yourself pulling on them. If someone wants them for whatever reason and have help for them, then knock yourself out. It's not going to do any harm. It's more for the guys that are on their own (like myself) or just don't want someone helping them with that, it's not necessary. Just keep up short, non energetic activity, even if it's just walking up and down a hallway, doesn't have to be outside. Walking will prevent issues better than any socks.