There are ways to mitigate certain things that folks think are requirements with dog ownership.
First, walking the dog so it can go potty. Teach your dog to go potty at home not during a 10-20 minute walk. I have never owned a dog, large or small, who required walking. Walking is a fun activity not a prelude to bathroom functions. When it's raining, my dogs can do their business in just a couple minutes in their own yard/campsite and come back inside where it's dry. They do not need to go to another yard or campsite to do so regardless of the weather. This makes it easier to deal with doggie business in the rain AND reduces friction with other campers (my dogs don't poop in or alongside their campsites). Walks are reserved for entertainment. An ocassional poop happens during a walk, but it's not a regular event that other campers are subject to.
Second, most dogs just want to be with you. They can usually handle less activity than people think. There are three types of large dogs: physically hyperactive (labs, aussies, etc.), mentally hyperactive (huskies, jack russells, etc.), and the rest.
Physically hyperactive need a ton of exercise to get to settle down. As they age this will decrease, but when young it can require a lot of effort. Only dog I ever had to crate was a 6 month old black lab who could not settle down at night because every single sound had her bouncing. Every other dog (any age) learned quickly to sleep at night and relax when inside. These dogs are hyperactive long into their adulthood. Their hyperactiveness tends to override their desire to please you. It is different than just being a puppy because it doesn't ease up with a 20 minute walk - they need to physically exhaust themselves to be able to relax for even a few minutes.
Mentally hyperactive are the most difficult. With these dogs, no amount of physical exercise will be enough. They need mental stimulation constantly. They need to use their brains - if you don't give them something mental to do, they will think up something on their own and I can pretty much guarantee you won't like it. They enjoy out-thinking you more than anything else.
For the "normal" ones, they love to play and take long walks, etc., but they will adjust nicely to a less active lifestyle. Their main desire is to be with you regardless of what you are doing and they will adjust in order to please you. They may be playful and enjoy a game of catch, etc., but they can relax even if they don't get it.