During Palin's speech at the convention Cindy was ecstatic. But, knowing woman like Cindy & daughter I can speculate that they have some animosity towards Palin. The former convinced that they are 'better' or more 'refined' than Palin when in fact the opposite is true.
The type of woman Palin is, (devout Christian, outdoors gal, bright, attractive and mother of Trig), somewhat puts women like the McCains off. Deep down they know Palin is a remarkable in that she celebrates rather than feels any bit of shame of how she leads her life and who she is. Cindy and the daughter realize it takes a very secure, confident and stable person to be like this, something they are not, so they look at Palin and bitterly quip, "how dare she be so good and not worry what others might think!"
...but, I could be wrong.