Yeah. I've often wondered that. BHA could charge £5 per car and people could then either train in or use the bus to the City Centre.
But maybe BHA are not interested. With the hotel build eventually they are going to need the car park for guests.
I'm not saying bus fares in Brighton are cheap but why should people getting free parking get reduced bus fares into the city? The standard all day saver which Withdean parkers buy is the same price for all adults in Brighton (except oap and disabled passes).