Certainly not defending them, but I bet I run into glitches like that at least twice a month trying to buy something and finally, very frustrated, just give up and don't bother. Even happened to me at Sam's Club when I was trying to re-new my membership so I could buy some tires. Finally gave up when it wouldn't accept something, or my e-mail was already in use, of course it is, I'm a member damnit.
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