but itll be under contract and prices are cheaper in US
so china is the where they will want to earn max profits
Nope you have that wrong. It's cheaper to get the phone but the phone cost more on contract.
Here's an example for you of a phone on contract. I won't even use a flagship, I'll use the Nokia 735.
I'll use my carrier as an example.
Nokia 735 - Free on two year contract
?30/m (equivalent tariff I use) - unlimited calls, texts and data
?18/m is what I pay for the tariff on SIM only
?12/m for the phone
?179.95 to buy the phone outright
?288 phone on contract (?12/m over 24 months)
?108.05 is the difference.
I'm not sure if this is split between OEM and carrier in some way but in the contracts I've had in the past they state the phone cost more so I'm assuming it's all the OEMs profit.