My 'local' (Malt Shovel Tavern, Northampton - 8 mile walk!) has had 40 or so on, but a lot of those were on a rack in the bar. Wetherspoons wouldn't have room - and the customers would indulge in 'self-service'.
I was in The Cordwainer on Tuesday - he day before the festival started - and my CAMRA voucher was refused. Apparently there's a 10p/pint reduction for the festival and it had been put on the systems a day early (the manager didn't know why - he'd found out that morning). Due to this the till would apply only 40p discount, so waiting until yesterday might have restored the full amount - he wasn't sure!
I might see what's in - MK has a good selection - but he Shovel has several good 'uns atm and the quality is excellent (W in MK is pretty good, actuallY).