We've had the fun with drug-dealer pit bulls. That fad died after the ban. Now we have unfixed, unsocialize big male dogs. The latest in our area is a King Shepard.
Big huge dogs let to roam free by road-rager types. This has led to a crackdown by the authorities on the friendly dogs who just want to catch frisbees (like mine!). The park is a dangerous place right now, and I hope this fad is going away soon.