If you're wandering around outside and decide to take a long rest at camp, I have no problem fast traveling there. Essentially, there is a waypoint in camp. Yes, I suppose they could show it.
One possible solution is you can only fast travel from one waypoint to another; you have to be in front of one for it to work. This could be the only time you can go to camp and long rest. That would be pretty easy to implement.
When I was in the hag lair, if I tried to go to camp I got a message that I couldn't leave from a dangerous area (I forget the exact words, but something to that effect.) I think this is a good way to help address the issue; traveling to camp should be off limits from more areas, forcing you to resolve situations before you can go to camp.
If your in the goblin camp, and have started killing their leaders (and possibly anyone else you can) I think it's broken to be able to take a long rest every encounter or two. That's a case where you should be prohibited from leaving unless you do it on foot, or through the waypoint. For example, if you leave after killing Gut, then come back, maybe you get a hostile reception when you return. Or security is way higher. Or there are more enemies you have to fight. You shouldn't pick back up exactly where you were with nothing changing after being gone 8 hours.
Ultimately, the 'long rest at will' mechanic of BG3 breaks too many things in 5E. I think they do need to address it.
