@heartshinegirl if you want the option to add somewhere to dwell while travelling to other worlds/before or instead of building a home but without owning a pack that includes tents what you can do is create a generic lot type and build whatever you want. So it can be a shelter or a hotel or wood cabins for example and you could even add a fishing retreat with the pond option. I also added a ruined piece of castle to sleep in too with nearby outdoor grill and public bathroom.
Using the base game only (as I don't know which packs you have) I added bars, a disco, a restaurant set (with food from the bar) and hotel rooms to a generic lot type hotel and it worked. Sims didn't pay for rooms but it still looked like a hotel and had the same elements. But it could actually be anything you wanted it to be. I also edited the local gyms to add sleeping quarters, although the busy gym did mean that the sleeping took a long time as it didn't kick into fast forward. It was better for naps.
Charity Organisers as you mentioned are also available but only with the city living pack in the political career path. With Get Famous, celebrities get to give back to the community too with donations of money or even by donating their possessions. The ability to give back to the town in a more hands on way and live sustainably is part of Eco Living and if memory serves me that's also where the Freegan trait is added to the game. That's a fun one actually, I built a whole furniture store from things I found in dumpsters.
I don't want to encourage anyone to spend money but if you decided to do so, Outdoor retreat is one of my favourite packs and my Sims often just travel around with a tent and a portable campfire. In the base game I particularly like travelling to the hidden areas like Sylvan Glade or the grotto in Oasis Springs. My Sims happily stay tucked away there for days just fishing. Snowy Escape also has a tent if I remember correctly. Outdoor retreat adds airbeds and camping cots as well and if you own Cats and Dogs, pet supplies are included. It also adds a stunning vacation world that I never get tired of visiting. But don't take my word for it, there are online videos, etc of Granite Falls to help you make your own mind up.
Whatever you decide to do though, these are all fun options. I really loved building my base game hotel!