I don't think pubs are appropriate places for children really, unless it is for a meal.
My dad lived/ran a pub until recently and my DC's were never taken in there, even though that meant they didn't see their Grandad very often
As for the Wetherspoon's rule - why would you expect to be able to look after children adequately when you have drunk so much you wouldn't legally be allowed to drive a car?
Some pubs are nice to sit outside in the summer though if they have a big play area.