So demand for SBD went up because it was the currency of the bots?

This can be supported by information regarding how much of the total supply of SBD circulates amongst the bots or rather how much of the SBD circulating is paid to the bots on a daily basis.

https://steemit.com/steemit/@penguinpablo/how-many-of-the-upvotes-are-done-by-paid-voting-bots#@mkdouglas/re-penguinpablo-how-many-of-the-upvotes-are-done-by-paid-voting-bots-20180314t124211980z