I agree that keeping Mr. C from sticking his foot in his mouth (insofar as that is possible) is in Charlotte's self-interest, but I maintain that is not toadying.

I can also agree that Lizzy sees self-interest in Charlotte's accompanying Mr. C to visit Lady Catherine; but again, that is not toadying.

Charlotte has her shortcomings to be sure, but I see no reason to smear her with "toadying," a term more insulting than she deserves.

While I do not wish to imply that Charlotte's motives are "pure," how many characters in P&P are acting from pure motives (and what a saccharin story it would be if they did)? Jane wants Bingley to love her. Darcy wants Lizzy to marry him or (when he sticks his foot in it) at least respect him (hence the letter). Col. Fitzwilliam wants to marry someone with a fortune. Bingley want to find a wife. And those are just the sympathetic characters. Who exactly in P&P is so pure that he or she wants nothing from anyone? True, Charlotte sacrifices a lot (perhaps more than she should) for what she wants; but the writings of Jane Austen appear to present a largely materialistic world. It's a miracle that love succeeds as often as it does.