Buying an unlocked iPhone SE?

So here s the deal, l bought a Verizon iPhone SE from the online Apple Store and had it shipped to my house instead of setting it up in store. My question is since all the iPhone s Apple sells are technically unlocked with the only difference being the carrier phones come with a sim already inside couldn t l technically just use my old Verizon nano sim from my 5C? Correct me if llm wrong but the way the carriers lock the phones is through the activation process so if l use my own sim and don't activate my new phone with the sim in the new phone wouldn t that mean l technically got an unlocked phone without paying fullprice?

Yes, you can use your old SIM card in the new phone, but how does that mean you didn't pay full price? You still have to pay for service and data from Verizon.