I imagine if we survey hard enough we will find people with defective genuine Canon-branded batteries too. People have even...perish the thought...made reports of defective CAMERA bodies from Canon!
If you have $15 batteries vs. $50 batteries and you buy 4 instead of 1 and 1 is defective and the other 3 die in 2 years instead of 4 years, should you buy only $50 batteries from then on? I suppose if battery reliability is paramount to all other concerns OK...
provided you know that the name-brand is actually more reliable than the cheapie (I await scientific studies vs. net.anecdata).
And as for warranty, who is so slavishly honest as to tell a wealthy multinational conglomerate what battery they were using when the camera broke? If that's an economically fair negotiation, you will be so rich as to view the camera as disposable anyway. Tell them you were using their battery by their instructions...it was most likely their fault the camera broke, not the battery's, unless the battery melted down inside there (more likely with a flash than a camera, and they don't restrict what AA's you put in a flash).
Canon should be rewarded for the hard stuff like lenses with our disposable income, when they've earned it. Making profits on ordinary accessories doesn't motivate them to do the things that will make a bigger difference to us.
Oh and btw I did see the USPS is banning
international shipment of LI-ion batteries after blaming two fatal cargo plane crashes on it since 2005. But I am skeptical both of that analysis and the motivations. I'm not sure they have real evidence what started fires on those planes. And why wouldn't we then ban it domestically too, planes are OK if they fall on our houses?
I can imagine this shipping ban as being essentially an import tariff on Chinese electronics. Taking the postal service out of the delivery equation may be protectionist for US-based retailers (who will buy from distributors using bulk shipping containers) over those guys on ebay from Shenzen who mail you stuff cheaply. That's what that ban may be about, it was just something the gov't could come up with that the Chinese couldn't nail them for. (Then getting taken seriously and scaring people into carrying on their batteries rather than checking them in the hold? Good grief.

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