Nope. Phones are fine. It is normal that the battery life should decrease with the option turned on. I have 9 friends over, and we just tested them, and yeah, there is an increase in battery drain which can be clearly seen whilst scrolling safari.

For the record, the battery life on either modes is stellar, but to dismiss the increase in battery consumption while on 120hz is just outright denial. I am still able to get two days worth of battery on 120hz, but then again, I prefer battery life over promotion. To each his own