I stick to Amazon for lower prices, more variety of products. Flipkart may have an edge over apparels though but I hardly buy such items online. Coming to return policy, it is combination of company policy towards customer service and also what kind of customers one is dealing with. There are rising cases of Return Fraud where a faulty item is getting returned to Ecom sites than the one actually purchased and refunds are getting claimed. See this link as one such example
India Business News: Consumers buying winter fashion and lifestyle products on Flipkart will get less time to return products as the Walmart-owned e-tailer is tightening i
timesofindia.indiatimes.com
I have previously known that in the US, several segment of buyers used to exploit return policy of Walmart by buying something and using it and returning it back within the stipulated time to claim full refund. People have done this for dresses, furniture, mattresses and what not. So retail chains introduced restocking fee which is still trivial amount being deducted from refund and that also did not put a check to it. Such things end up eventually in impacting return policies and responsible customers end up suffering.