Not irritated with the kids themselves, but the parents who let them "play shops" while everyone else is queuing.
In the supermarket the other day, a woman was letting her five year old scan everything through the till and it took forever.
Child was fighting when she couldn't scan something and mother tried to help, screaming that she could do it herself - all the time everyone in the queue is getting more exasperated at the time it's taking.
I've seen it so often, are some mothers just ignorant to everyone else wanting to pay for their shopping and get home? Or is it just me and should I cheer as their little darlings have a temper tantrum because they can't scan through a bag of pasta bigger than themselves?