its all perfectly legal whenever someone pulls you up just say you're going to a blm protest and they will wave you through with encouragement

Seriously, if a cop made this into a fine, I would assume- actually, know that he didn't surf, tell him he might need some form of assessment by a man in a white coat and obviously get a a fine..... but would still leave the boards in the car! If surfboards in cars are illegal then coins in the cup holders should be also!

Why won't soft racks work?

Just secure with seat belt over the top and all good

Rules on load restraint
You must restrain any load you are carrying on a light vehicle so that it:
- Stays on the vehicle during normal driving conditions. This includes heavy braking, cornering, acceleration and even minor collisions.
- Doesn't negatively affect the stability of the vehicle, making it difficult or unsafe to drive.
- Doesn't protrude from the vehicle in a way that could injure people, damage property or obstruct others' paths.

You must pick up any fallen load if it is safe to do so, or arrange for someone to retrieve it.

There are two main load restraint methods
Tie-down restraint:
- using lashings to clamp the load to the vehicle (relying on friction for most of the restraint forces).
Direct restraint:
- Containing - the load is contained within the vehicle
- Blocking - the load is blocked from moving by a rigid structure, e.g. a rated headboard
- Attaching - the load is attached to the vehicle