I once walked into a T-mobile store, showed them my phone and claimed that the simcard is stuck and asked them to transfer it to a new simcard I brought with me

I once walked into a T-mobile store, showed them my phone and claimed that the simcard is stuck and asked them to transfer it to a new simcard I brought with me. They asked for my phone number, scanned the barcode on the new simcard, done. I didn't have to provide any identity. I could have been anybody and the only trace would be the security camera in the store.