What you are describing is the classic cycle of retail business. Management pits employees against each other to sell, and then when business dries up, they blame the employees, fire them, and hire new ones, in the bizarre belief that somehow the new employee will be able to do what the old one could not: sell to an empty store.
Unfortunately, it's perfectly legal. Your true recourse is to get out of retail -- get a better education and a better job, get into management, or find a sales job that generates greater commissions -- because, as long as you're being beaten up to "sell, sell, sell," you may as well get paid better for doing so.
Hope this helps.
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