I would not go either. Even without Covid.
If you buy the ticket and visit a decent Auto Show with the intention to check out some cars - no one will tell you are not allowed to sit in a new model Hyindai, MB, Toyota, VW etc just because someone bought it yesterday just like in a next door car dealership. I.e. you get what you paid for.
Here, it is not a Boat Show, it is just a annual market with entrance fees and a paid walk along the marina.
Just my opinion, based on my experience.