I have lovely lumpy heels caused by wearing ill fitting, unsupportive shoes as a child/teen. I find it hard to find shoes that I can comfortably wear, now, as my right heel is so sensitive to touch.
And the people bleating on about not having to buy expensive shoes - try having kids who need an H fitting and not spending a fortune. Thankfully, DS1 has slimmed down to a G fitting, as a pre-teen, but with hypermobile feet, I'm still shelling out £40+ at a time on sufficiently supportive trainers for him, or else he ends up in a lot of pain in his feet and knees caused by his feet rolling inwards. Even his wellies are crocs, as they have arch support.
I agree with you about the quality of Clarks, OP. Their trainers have lasted OK, but their school shoes fall apart in no time. The ones that haven't come apart at the seams have worn through the soles in about 3 months. We've had a much better hit rate with Geox, for DS1, and they are much better at preventing his feet from rolling in. He refuses to wear start-rite but DS2 loves them and often puts them on in the house - the last pair of Clarks he has, he was kicking off in the street because they were so uncomfortable.
Another thing I've noticed with cheaper shoes (child or adult) is that they're so heavy. I find that really uncomfortable.