Heels on wheels

"Please be aware lowering of under-carriage and deployment of wheels concealed in the heels of certain training shoes may cause offence, and is not welcome on these premises. If used, the offending footwear will be seized, and a pair of soft slippers of appropriate size offered in replacement for your comfort during your visit. Management do not guarantee condition of trainers on return". I'd love to see that sign, or something similar, in the shops.