I get that but saying they don't use them is misleading.
Yes I can slap in any GSM network SIM and it will work in my Verizon one. If you slap in a Sprint one it won't work but not because of the phone not taking SIM cards... But because Sprint won't allow it on their network.
I slap in my Verizon SIM or any other Verizon SIM and it will connect up to Verizon with the information/number on that SIM card.
Yes other networks like AT&T, T-Mobile, and Sprint have to get their phones unlocked for GSM use outside the US (or even inside). Verizon is the only one SIM unlocked but that is due to an agreement for spectrum they did in the past -- not out of the kindness of their hearts.
All in all though -- I was simply saying yes CDMA phones do use SIM cards. They use it to connect to their network just as much as GSM carriers do.

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