Actually - the shoes/booots in the advert are too big for the model, there's a gap round the shin of the boots. If she walked her toes would get smooshed into the toebox and look like a BankRobbers Face in a pair of tights.....................................................
Which is why I would LOVE clear shoes to demonstrate to my 
patients just exactly WHAT their shoes are doing to their poor feet.
I show them the lumpy bumpy bits where their feet have pushed a cavity in the upper.
Or I draw round the shoe then round their weighbearing foot (which looks different to non weighbearing) to show the difference and the only way they fit is for the toes to curl and overlap.
Cinderella did not have glass slippers they were fur (the French for 'glass' and 'fur' was mis translated) otherwise Prince Charming would've run a mile.
Clear shoes - not plastic though eurgh...Bring Them On.