Conditional moves in Live Chess

I love conditional moves. Why can't I use conditional moves in Live Chess?

For example this 1 minute game:

being able to enter the conditional move IF Qf8 THEN Rxf8 would have made my life so much easier ...

You don't need conditional move on that. Just premove Rf8. The only legal moves are Ne8 and Qf8; the former will make your premove illegal, so nothing happens, so you can play Rxe8.

Yes, sometimes conditional moves in Live Chess are good, but then again in OTB play there's no such thing as conditional moves, only "a move played immediately in response of seeing another move" which still takes a little time to execute.

In an OTB game, are there conditinoal moves? By adding conditional moves here you just make the difference between OTB and online ratings bigger.