You don’t necessarily need to get two straight away, though. If you’ve been a couple times and used the hire shoes, sweet. You’re getting into it, you reckon you’ll probably keep going, time to buy some shoes. I’d actually advise against it. Climbing shoe rubber varies from soft to really bloody soft, and you dragging it all over the wall wears it through really quick.
So I’d suggest spending quite a few sessions in those hire shoes, really focusing on your footwork. When you can confidently stick your feet first go while climbing, and not have to adjust your feet constantly, you’re ready for your own shoes. Shred someone else’s until you are confident you can make yours last.
My understanding is that cookies were generally just used as a fingerprint- it’s just a unique ID that is used to tie your device to their database, which is where the information is kept.