Sounds like a massive rent seeking scam to me.

From The Guardian:

Countries and organisations planning to host events at vital UN climate talks in Glasgow next month have said they fear that increased costs at this year’s event will cause problems for developing nations.

Multiple participants said that the cost of renting Cop26 pavilions – event spaces for hosting workshops, panel discussions and keynote speeches during the conference – is considerably higher than it was at Cop25 in Madrid, with some saying it had increased by as much as 30%.

Organisations say they were told that a combination of Brexit and the pandemic were to blame for the high costs. It comes after the Financial Times reported that one organisation was quoted nearly £500,000 for its space.

The total rental value of such a site relates purely to how many 'customers' you can meet and how much money your wring out of them and/or how much 'greenwashing' you need to do. Sure, post-Brexit, wages for skilled labour have gone up (that was an argument FOR Brexit) but the real costs come off the total rental value to give a lower pure rent. If the real costs were more than the total rental value, nobody would want to exhibit.

So neither Brexit nor the pandemic were to blame, the rents here are a function of how much money is sloshing around the whole 'environmental-industrial complex'.

(As Treasurer for the Labour Land Campaign, I had to sign off a payment for our stand at this year's Labour Party conference, that was a couple of grand just to have a table with leaflets for two or three days. If - big if - they can drum up a hundred new members chipping in their sub's for a couple of years, it was worth it, in purely commercial terms.)