I used to go to Towcester races regularly about 30 years ago, so probably not awfully relevant, but I never had trouble from the course but did have a few altercations with one particular pro who wouldn't accept that I was merely taking shots for my own amusement. He was quite adamant that I wasn't allowed to take photos without a pass.
He even complained to the course, and dragged this poor guy out of his office to 'have a word'. After I had a chat with the course representative the pro was told to politely and forcefully to 'grow up'. Having been taking photographs on and off for over 30 years this is my one and only run in with a pro photographer, others have been at worse dismissive and at best friendly, informative and encouraging.
So take your camera and be prepared to freeze you butt off and post up your pics in the new year.