I've had the same experience as Lisa, but I'm in the same area. I have trained with and/or trialed at eight different SchH/protection sport clubs in the past five years. I've never once felt the club was being hostile to me. Because the group I originally trained with was not a sanctioned club, I've never had the luxury of trialing with my own club/home field and often have been the *only* person in the event that was not a member of the host club and usually those clubs happened to be the most welcoming towards me. A while back I signed up for an event at a club in a really rough area. As usual I was the only non club member participating. This was a club of big, burly guys that all owned Rottweilers and Cane Corso type dogs. Their TD has a reputation for being very militant in his training style (toward the people not the dogs). Here I was with my little GSD bitch 50lb soaking wet, the only female (human) entered in the event, the only visitor, only one year into dog ownership and training but these guys were some of the nicest and most welcoming I have ever met.
I find that clubs who are training on public land or land they don't own tend to be the more "secretive" type and it's usually not why people think. The group I used to train with did not own the land we trained on and were receiving a huge favor from a local police department. We also sometimes trained indoors at a facility also receiving a huge favor from that owner. As such we had to be much more strict about when we could allow visitors and who those visitors were. We could not just let people come and go as they pleased since we had to be responsible for who was there, not only for our own sakes but for the people who actually owned the facility (and the liability). I used to coordinate the visitors and let me tell you for every 20 people that contacted me we had maybe one ever show up. We allowed visitors once a month and always gave them directions and made it very clear when/where to show up and almost all of them never did. Our priority was our members first so we could not be distracted by a revolving door of people coming and going as they pleased with no real commitment to the club or the sport. Most of the clubs I have visited or trained with have been extremely tolerant of these types of people, moreso than I am!
Lies, I think it makes a difference if you are already in the sport and if you aren't.
One thing I have noticed in SchH is that the people here on the forum are an exception with being involved in so many venues. A lot of times, if you are doing RH or Flyball, Agility, Obedience... these people are smiled upon and not in a good way, especially by a lot of oldtimers who just don't know any better.
If a dog isn't good enough for SchH... just sell him to do RH, that he'll be good enough for. They don't take anyone else serious but themselves.
Also, what you perceive as friendly and outgoing may not be perceived as friendly and outgoing for an outstanding person that doesn't know the sport.
The sport does demand a lot of discipline and that discipline may come across as rough and hostile. That is why outstanding people have such a big issue. Also, if SchH people do not take other venues serious. And the way I grew into it, offering Flyball on a SchH field, IS an exceptional thing and very open minded. I've never even seen anything else except for basic obedience lessons, maybe Agility or RH.
Clubs change, but it is a slow change. Maybe Germany can actually learn something from the USA. And I mean that.