Thank you for your questions. My theory is this.
Cryptocurrencies can be divided into "weak" and "strong". Unfortunately, I consider Steem to be a weak cryptocurrency (so you have to do everything to make it strong) and say Bitcoin to be strong.
A weak currency is actually much more likely to be sold by people on exchanges (e.g. stores), whereas with a strong one such changes are less noticeable.
But what I think this is due to - the fact that Steem has no stores, entertainment. Instead, it has basic financial systems. If Steem gets back on track, it is likely to get stronger and stores of all kinds will try to store more Steem than sell.