^ I agree actually.
In Pakistan, in Punjab for example, everyone speaks the same language, religion (mostly) and culture. So to say that marrying within the caste is to make the marriage "easier" is slightly dubious.
Actually, what's closer to the truth is many people see themselves as better than people from other castes and so wish to marry inside their own caste to keep their progeny 'pure', a concept about as far from Islam as you can get.
Totally agree.
Someone in an older thread once mentioned it reminded her of old Nazi ideas about keeping their bloodlines pure. Sounds shocking when u think of it that way but have to admit I can't see much of a difference between our caste systems of marriage 'within our own' and their ideas of 'purity'..