In Scotland we've long since lost our motorshow. The last one was mainly filled by one of the big dealers showing off his own stock, with other small garages helping out to cover over marques too. Very little in the way of big manufacturers were there.
As for the shows in Excel, a friend did go to one and wasn't impressed. Said those in Birmingham were better. More manufacturers that you'd like to see at a show. Now he flys out to Geneva Motorshow instead, which he tells me was far superior to anything he's seen in the UK. And from where we are you have to fly to see a show anyway, so why not go for the best you can?
But for the UK you have to have Ferrari, Lambo, Aston etc to bring people in, and you need the top German brands there too as that's what sells in the UK. If you don't have those, you don't have a show. And let's be honest for the likes of Ford and Vauxhall etc, and this is no criticism of their brands, you can nip in to your local dealership and see just as much as you'd at any motorshow.