It wouldn't even be understandable if the connectors were frequently all in use. This is a large multi-storey car park, in a city that has a Low Emissions Zone. Less than 1% of the parking spaces have charging capability. If they need more, they should install more.
I think it's likely that most EV drivers charge at home and don't come far enough to need to charge in that car park. I'm 50 miles away, and I wouldn't normally need to charge there, at least in summer. I think that's why they aren't more used. But stuff happens. I needed the chargers in May because I had to drive on to Largs after visiting the theatre, spend the night in a hotel (which didn't have EV chargers) then over to Cumbrae on the ferry, attend a funeral, back to the mainland and 70 miles home. The obvious place to charge was in that car park, while I was at the opera. It was only Carmen, not a particularly long piece, but I was 3 hours and 35 minutes. My friend had asked if I wanted to go to dinner before the opera, which would have been nice as I knew I'd miss dinner at the hotel, but I didn't want to have to leave the theatre at the interval to go back to the car park and unplug the car, so I declined. Great for bringing business to the city centre I don't think.
I might need the chargers in winter, I'm not sure how the SR will perform in really cold and awful weather. Far better to charge in the car park than stop for a top-up on the way home. But also not fun to have to leave the theatre in that weather to unplug the car during the interval. Especially since I'll probably be the only car on the eight connectors.
They need to stop with the overstay fines and let people stay as long as they need to be there. And if it does start to happen that all the connectors are occupied, they need to install more. They have completely the wrong attitude.