Energy, you never know what Park employees are thinking about or what they might have been told such as an undesirable the State police are looking for etc. My wife and I haven't been doing her favorite hobby in several years but she wished to visit every National Park in the USA. We love the Parks but I'm afraid I'm a living room camper. Always a hotel/motel or cabin. My favorite is the Grand Canyon. To me that is a place me alone with that canyon is my internal soul. I will add if anyone else has stayed for a weekend or at least 1/2 day and has done so like in 1980's, 90's and then around 2010 you know what I mean (at least) the South side how damn much that place has changed over the years. Yellow stone has more things but my Grand Canyon is all mine
It is also cool to take the train ride to the Canyon too. We fly to where ever we go but next time I ship my conceal carry items, don't trust the airlines.