AFAIK many retailers (Target, for example) use an identifier derived from your CC number and don't even need your email or phone number to build a profile on you.
I totally agree with being concerned about your privacy, but I don't understand the increased harshness on this service specifically as opposed to the already-pervasive services that already collect your data on a daily basis. Is it just because this one is Amazon and it's fun to hate on them?