I hear ya ... some people just see GSD and freak ... especially if the fur's up ... OMG ... they MUST be getting ready to attack ... quick hide everyone!!!
I'm sure if you take it slow, it'll be fine ... but it all depends on the type of dog park you have! Like I mentioned, mine is huge, and I can walk around and avoid the "crazies" and just do trails.
Marionís Zoo-Kyleigh, Raylan-cat, Echo-TAG,