Imagine you are the supplier, where is your responsibilty to your customer. They have problem, do you just push away. Come on man just be a responsible guy to everybody including yourself.
Did you ask what their policy on warranty on manufacturing defects? You obviously did not.
If you did, you would be told that it's 7 days 1-to-1 exchange, and it's Canon Singapore service after that. Maybe you are new to Singapore and had this misunderstanding. One may split hair whether this practice is good/reasonable or not, but this is not something to argue AFTER you bought the item. Your buying from them implies that you understood how the warranty works, especially in a clear-cut case like this: majority knows what the policy is and has been for years.
Alternatively, you could have bought from a shop that offers "shop warranty" for cameras. Ironically, they sell stuff comparatively CHEAPER. People seem to pay more for the very "feature" that you deem undesirable: to have Canon responsible for warranty rather than the shop.