Large-scale manufacturing of any kind is bound to result in at least a few defects. It is up to the company how to handle them. Some disregard these errors, other get users tied up with annoying and inexperienced customer-service staff, while yet others actually look at helping the consumer.
Apple seems to be the latter, since it has announced that any iPhone 6 Plus being sold between September 2014 and January 2015 with a defect resulting in blurring photos would be eligible for a camera replacement that is valid till three years after the retail launch date of the iPhone 6 Plus. The eligibility check is done by verifying the Serial Number.
The free camera replacement is applicable for Apple Stores and official third-party partners.