"So what? If hungry enough, and don't have milk for cereal, there is room at my table"
We had a similar experience years ago when we were tent camping in Fundy National Park, when it was just the hubby and me. It was raining (as usual) and we had a tarp set up (as usual). There was a dad in the site next to us with no tarp and he asked if he could stay under our tarp just long enough to eat. Of course we said yes. We noticed they were eating dry cereal and asked if they wanted some milk to which they gladly said yes. Their milk had gone bad. We chatted for quite a while, until they had to pack up and leave.
We were also in a situation many moons ago (tent camping still) when we were surrounded by a huge family who had booked sites all around us, long after we had booked ours. After they arrived and set up they apologized to us because we were stuck in the middle. We just said no worries. They had set up a volleyball net and immediately invited us to join them, including their cookout lunch. We accepted and had a great time. Large groups aren't always bad.