@Whowhatwerewolf - I agree with @ScottishMouse - the exchange events used to be ok, but now you are expected to hand things over without being able to see if there is anything to swap that suits you.
It seems very likely to me that this change is to expedite the acquisition of lots of lovely items which, if not swapped during that event, reappear as Reworn items for sale on the website in the not too distant future.
I have, however, been to an event under the new regime and DSis has been to a few recently.
This is what we do:
Hand over one item that we frankly don’t care about and aren’t bothered about trying to sell, and get a ticket.
Gain access to the swap rails and see what is there.
If there are nice things available, mysteriously rediscover extra items at the bottom of your bag and hand those over for more tickets.
If the rails look unpromising, do the best you can with your one ticket and take all your other stuff back home with you.
DSis went to a brilliant one in central London a couple of weeks ago, but the one before that she said was rubbish.