I love the way you managed to present this issue in it's various aspects.
I must admit I got happily surprised that you even included the 'cognitive bias' aspect. When it comes to addictions, many people seem to forget or the very least underestimate 'the power' of the cognitive bias.

Another brilliant article !

P.S

Oh dear, if I replace the word substance by Steemit it looks like I am on my way to become a Steemit addict!

Aren't we all? :p

P.S.S

Conclusion:

In the end we are all 'dopamine-junkies'.