Should. Not will. And how is it false advertising? His battery did, quite clearly hold up to 80% of its charge, up to 1000 cycles, up to 5 years. The link stated doesn't guarantee anything. The reason you wont link me to it is because you know, full well, that it doesn't exist.
As I have explained, if you use a battery quicker, it will not last as long. So it is perfectly normal and expected for a battery to die after 3 years and 900 cycles (show me another laptop that would be able to achieve that).
He's not entitled to a free battery. If he had used a nicer attitude in store then he may have got one as goodwill, but if that didn't work, then he's just going to have to buy a new one. Arguing on a forum isn't going to change that.
Wrong again.
The reason I refused to link you to it is simple. It's been linked and quoted before. But here it is again to satisfy your curious need for something that is both obvious and explicit.
"The built-in battery of your MacBook Pro or MacBook Air is designed to deliver up to 1000 full charge and discharge cycles before it reaches 80 percent of its original capacity. In addition, Adaptive Charging reduces the wear and tear on the battery giving it a lifespan of up to 5 years."
Nowhere, does it say 'up to' 80% of its original capacity. It clearly states that up to 1000 cycles with only diminish the battery by 20% - not cause it to swell and fail completely. There is a significant jump, in print, from '80% of capacity with less than 1000 cycles' to 'dead with less than 1000 cycles', and this is why Apple didn't state the latter.
Stop defending the indefensible.
The OP is entitled to a new battery at no cost.