Mr Gardiner and Mr Bingley's father had much the same social standing. The Bingleys are from a respectable family in the North of England whose father had made a fortune in trade: Mr Gardiner would also be classed as respectable, and he is busy making his fortune in trade.

The Superior Sisters have done their best to forget it, but we can be sure that Mr Darcy (part one) has not. His comment about the Miss Bennetts, that their connections would damage their chances in the marriage stakes, could equally be applied to the Miss Bingleys (and quite possibly was). His arrow goes straight over their heads.

Here is JA being subtle again -- so subtle that the adaptors of P&P2 missed it entirely.