Originally Posted by
GodAtum
Odd, I have ridden on the pods a few times without paying for parking. I just like the experience.
What he means is that HAL expects that people who are using it are parking and therefore paying to park.
As there's big fences around the car park you can't really use it for much else, except for riding it for fun.
So Thistle comes up with the idea of the gate, now there's a second legitimate reason to use the pods and therefore HAL will want cash to support this operation.
Presumably the amount of people who use it just for fun are small enough to not worry BA too much. Putting in infrastructure to charge them would probably cost more than they earn.