There's Expo Costs and then there's Expo Costs ...
All depends on what you're getting, where you'll be, and at the end of the day, its a value for money decision for the purchaser.
For example, at the World Solo Champs and Scott 24 Hour in Canberra, Australia this year, there are 3 main areas in the centre of the event village
. Sponsors. They get prime position and their site size and fitout is by negotiation.
. Expo Sites. These are $3500 and that includes a 6m x 6m marquee with power, light, heating, tables, chairs. At an Expo Site you can conduct trade (ie, sell things). These are close to the centre of the action, but not as close as the sponsors.
. Team Sites. These are $2000 and also include the same fitted out marquee package, but you can't conduct trade. You can give stuff away. These are the further away from the centre of the transition action.
Ultimately, its a decision for the organiser about pricing. These sites cost $$ and servicing the site occupants also costs $$. But, having an empty event centre also detracts from the feel of the event.