You're asking questions which link up with each other. So far the Naked European Walking Tour has always been in Austria, but we did have some talk about whether it should move to Germany or Spain, for reasons which will become clear! There are in fact far more than a dozen people on these trips, typically somewhere around 30. That limits the number of houses that can be found to hold everyone, and because Austria isn't as liberal in its outlook as Germany, not all owners are willing to rent to a nudist group. But there's a particular story here.
My first NEWT trip was in 2014, and the week started off with Richard Foley, who originated the event, having to take his dog to the vet on account of sore feet. So he missed the first day of walking. But he left the instruction with us: “Just don't be naked when you're on a paved road. Anywhere else being nude should be OK.” So off he went, and we started off on our walk, and soon enough we found ourselves on a paved road, and there wasn't much traffic, and someone decided that maybe being naked wouldn't cause any problems. Pretty soon most of the group was naked, and I'm afraid I was one of them. Well, a few cars did pass by, but nothing seemed to be wrong. The trouble didn't arrive until the evening, and then Richard addressed the group much like God spoke to Adam and Eve: “The one thing I told you not to do, you went straight out and did!” Apparently what happened was that someone passing by saw a group of naked people on the road, and called the police. The police didn't find us, but they asked around in the neighborhhod, and they talked to various people and finally located the owner of the house, and the owner talked to Richard. No, there wasn't a police raid (it's not America) but the message got through. It was a little embarrassing, but it seemed to be ended with that one day.
Now forward to 2019. Our organizer was having trouble finding a house to rent, and he had the idea of going back to the place we rented in 2014. And to avoid awkward discussion, he didn't tell the owner that we were a nudist group. Well, the owner got one look at a few of the first people to arrive, and he got pretty annoyed (I got this from hearsay--I wasn't an early arrival). He said, “Oh, you're those people from 5 years ago, the ones who embarrassed me with the town council! Well, I don't want you going naked around the house!” And apparently he also said “I can't control what you do away from the house”, which didn't make much sense since it was behavior away from the house that led to the trouble before, but anyway, he was telling us to behave ourselves on his property. And so that's why Roland, and all the rest of us, wore clothes in the house. And it's also why there was discussion about whether NEWT should happen in some country other than Austria.
Now aren't you glad you asked?