One of the Kung Fu clubs I went to shared a large sports hall with a trampolining club - the owners put a half height divider down the centre line of the hall to separate the areas allocated to each activity.
What this meant, of course, was that as we were very seriously doing our forms, people would appear briefly over the divider, before dropping down again, only to reappear, and so on. It was oddly surreal, and I've had a bit of an affection for trampolining ever since.
(A kickboxing club I went to after that had its booking directly after a circus skills club - we'd be going in as people were riding out on unicycles, juggling &c That was quite incongruous too).