I replaced a few Bradford Whites (the ones with old styles burners) under warranty, there is a mandatory upgrade fee for the VIFR unit which does come with a fresh warranty. Now if it a VIFR unit that was defective, when replaced it will just have the remainder of the warranty of the heater it replaced.
Now only time I ever got hit with paper work fees by the supply houses is when I am not the one that originally purchased the heater. I as well as my customers find this annoying. Also with Bradford White, AO Smith, and Rheem suppliers I always end up paying for the warrantied heater and get reimbursed when they get reimbursed. As for State water heaters, I never got charged paper work fees and they never charge me for the heater. They do have the upgrade fee as well though.
Very, very, bad ideal ! ! !
On putting blanket on gas water heater, because you must make sure not to cover "any" air openings and with the side vents it's very easy for the blanket to slide down blocking the air inlets, and according to the law you are required to post all "safety" warning labels on the outside of the blanket
all above reasons why mfg's make extra installation water heaters,
The funny thing about warning labels is that the people that should read them don't and the people that know enough have read them. The real reason why they are there are for liability reasons. For a plumber, it would be a bad idea to cover up that label for a customer for liability reasons. I will take this into consideration before buying an installing a heater blanket.
And then some manufacturers put a sticker on the heater "do NOT use an insulating blanket on the heater".