The minority attack is one of a few themes in the Sicilian. I have found the two pawns in the centre getting to roll forward if when white's usual attack subsides, to be more common in practice. Having said that you can't impose thematic idea on positions that don't suggest themselves.
Black's queenside advance often is highlighted and dynamically so if white castles on that side. Also the advance is just not about pawn structure but jabbing at white's piece's that support the centre; attacking a knight on c3 that is defending e4 for example.
My own take on the Sicilian is that it's about nurturing the central pawn majority, with flank action being the sideshow Bob of the overall action.
The minority attack is seen in a more classical form IMO in the slow burning white queen side advance in the (mostly) closed centre of the QGD exchange variation. The more open nature of the Sicilian accentuates the tactical play of the pawn minority rather than their strategic role with a closed pawn centre IMO.
I thought the minority attack was the undermining of a pawn in a pawn chain with one of your own pawns to either 1) produce an isolated pawn or 2) produce a backward pawn on an open file.
However, most Sicilians don't end up with a pawn chain. Apparently, the idea is to put pressure on the pawn at e5 (to get White to play Nc3) before advancing the b-pawn. However, I play the e6 Sicilians - what should I do in that case (since d6 and Nf6 is usually what gets White to play Nc3)?