I have found prices varying a lot between sellers in flipkart. And flipkart most of time shows its own seller(WS Retail)'s price. So such a feature will be nice.
I read a Quora post by a Flipkart employee who said that the seller chosen on the home page is often the most trusted seller. I doubt if people would buy from sellers with lower ratings. Nonetheless, a feature to consider all sellers before notifying prices would be nice.