We've had a few party invites (kids are pre-school-aged) that say things like 'no need to bring a present' or 'presents not needed'. We had one of these before and took it at face value, but when we turned up almost everyone had brought an elaborately wrapped present that went on a present table! It was pretty embarrassing - luckily I'd taken a kids' book along just in case (not wrapped - I've no idea why I didn't; I was probably going for casual...). What's the etiquette around this; do you just completely disregard the invitation and bring a present anyway?