The problem is, whether Alton charge a booking deposit of a £1 or not, it is not enough to deter people from making a booking (or a multiple of bookings) and not turning up, which takes away from those that genuinely wants to go but can't because all the allocations have been snapped up.
If you start to charge a deposit of a higher value to deter people for making false bookings, this will obviously rub pass holders up the wrong way as it means that they will paying twice to get in.
A refundable deposit would be the way to go.
Even if you did pay a deposit, unexpected things do come along and there will be times where you make a booking and for some unexpected reasons, you are unable to attend.
Limiting people to one booking at a time, could also prove problematic for those that like to make a short break form visiting by staying at a local B&B/Hotel off site.
For me, I'll be staying away and not renewing my pass until this pandemic is all over. It will be Merlin's loss, not mine.