Most customer service reps at these companies have no idea what their talking about. I'd say most of these people are not very technical AT ALL and they're just taught to read from a script or something.
I don't trust anything sales reps/low level customer support reps say on the phone. While that sounds cynical, 90% do not know what they are talking about. I'll grant that once in a while you will get that 10%. I always try to get info online, where at least if it is wrong you can point at it.