Think it started with the supermarkets following Wal-Mart's acquisition of ASDA. They started doing it, so the others followed. This spilled over to most other areas of retail
Anecdotally, the Jordan brand bring out a new pair of trainers every Black Friday, and this has had the effect of pushing trainer retailers like Size/Offspring into the fore with it all
Think it started with the supermarkets following Wal-Mart's acquisition of ASDA. They started doing it, so the others followed. This spilled over to most other areas of retail
Anecdotally, the Jordan brand bring out a new pair of trainers every Black Friday, and this has had the effect of pushing trainer retailers like Size/Offspring into the fore with it all
Tl;dr = because neoliberalism
/csb