When? 2017-18?

All throughout Steem's history. There have always been buyers. There have always been people with SBD sitting in their wallets because they want some stability of value.

Real demand is when people look for an asset because they will have some actual use for it.

Yes, and wanting value stability without needing to move off the platform to get it is real use.

Tell me one thing you can do with SBD besides buy and hope that the price will go up so you can sell with a profit.... Just one...

Simple. Hold it so that the volatility of your holdings ON THE PLATFORM are reduced (not have to deal with exchanges, fees, KYC paperwork, etc.)

Speculative demand is fake demand

None of what I described above is speculative demand.

The primary value of SBD is that its value is a lot less volatile than STEEM (even in its current not-quite-working-perfectly form, but the more that can be improved, the more value it will have).