Ask HN: Are misleading sales tactics rampant on Steam?

Here in the UK I was under the impression that to claim that products are on sale, you should show the previous price and should have been selling at that price for a meaningful period of time.

It appears to be rampant practise on Steam to list an item and put it on sale almost immediately. I understand why sellers do this to attract more attention to the product, but ultimately I don't think it genuinely serves sellers and buyers positively.