I think it's past time for another Stupid Questions thread, so here we go.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Please respect people trying to fix any ignorance they might have, rather than mocking that ignorance.
I think your answer is in The Domain of Your Utility Function. That post isn't specifically about cryonics, but is about how you can care about possible futures in which you will be dead. If you understand both of the perspectives therein and are still confused, then I can elaborate.