What is a better URL design for an e-commerce website?
http://example.com/shoes-women http://example.com/shoes-women-red http://example.com/high-heels-red http://example.com/high-heels-red-size-7 http://example.com/anne-klein-high-heels-red-size-7
http://example.com/shoes/women http://example.com/shoes/women/red http://example.com/high-heels/red http://example.com/high-heels/red/size-7 http://example.com/anne-klein/high-heels/red/size-7
I guess the reason why most of the big e-commerce sites using the URL design with slashes is that the are more maintainable (except Amazon, they use a mix). By using only dashes as a big e-commerce website it is possible to get fast into problems.
The SEO argument "you have to use forward slashes because Google likes folder-structures or topic-silos" is nonsense. Google does build its own structures by analyzing the internal linking structure of your page.