by the end of the book, since it is written more from the point of view of Lizzy, is that Mr. Darcy and his friends had some relations for whom there was some need to blush! But I think Lizzy discounts this due to her, perhaps, humility in being elevated to consequence and wealth and adoration of a man who is worthy to be loved back and who has these things. The people who could be blushed at are namely - Lady Catherine, her daughter, and Mr. Hurst (Bingley's brother-in-law - although it some ways - I'm just thinking of his rude behavior - and envisioning P&P2 and his sleeping on the couch ;)). It doesn't matter what income level one is - there will always be relations for whom one can blush! It's just that the money dampens the effect somewhat. :)