i wouldn't classify religion as primitive personally. i see it more as a necessary evil of sociological means to carry on information about spirituality that is beneficial when not viewed through fundamental eyes.

for instance... forms of meditation like Vipassana (buddhist awareness meditation) is an amazing tool for both spiritual and completely "natural" reasons. the religion of buddhism has developed this method and carried the tradition on that people today can benefit from. i practice it yet do not follow the religion. if it weren't for the traditions in the religion this information would not have survived and been refined so much over the years for the benefit of people today.

religion = necessary evil