I mean, I get where they are coming from. Like nobody is stopping you from traveling across your country/as far as you can go without a passport. “Anyone” physically fit to do so can quit their job, lose their home and walk. You can try to catch and cook your own food. Or scavenge and beg. You can see sights and explore nature for free.

All that being said, that’s obviously not the type of traveling people want to do. It works if you’re already broke and young and fit (and in some countries, not a minority), but if you want to keep your job and go other places quickly, that shits expensive and the OP knows this and is just being pedantic by saying all you need is courage.