MN, you need to refresh it, it's wrong to say 'Vedic Aryan tribes invaded 'India'.'
secondly, you suitably forgot 'shakti' factor in vedas; to blame vedic scriptures is purely incorrect,
I say, this practice is not inherited from vedic ages but is the result of socio-cultural changes happened in last 1000 yrs heavily influenced by external cultural influences (read arabic/persian)