Concessions are like deeds. If you have one for that area, you can establish your camp as a semi-permanent hold that you alone can access. With this, you can install your own equipment better than that found in towns, and more easily access a wider variety of resources. It becomes like your personal town, where you can have a forge, workbench, mine, inn, etc. Since the camp tools are constructed by players, they follow similar power options, so imagine what you could accomplish with a 40 strength forge.
There's been talk about the guild, but it's expensive. Namely, it costs 15 gold to open 5 member slots, and then ENORMOUS effort of construction to raise the cap or construct anything. I'd personally be willing to dump nearly all of my player effort into guild construction and bettering, but it's a hefty investment and is slow to pay off, really meant for you to become an experienced member before even being a member of a guild.
Once we have some personal sway, it'll prove a good way to concentrate our efforts and better corner the market, but right now a big deal is simply raising your own skills and your private camps. The faster we can level up and start making money, the faster we'll be working towards a guild. So for right this moment, the best way to help the group is to exchange tools and resources and make sure everyone is advancing as quickly as possible.