no, u must be dealt into the hand, but do not have to see a flop.

on .10/.25 full ring u see 10 hands for .35 x 12.5 (125 raked hands) = $4.37

So, ur paying 4.37, to get $25.

But, the way i played (Push all AA KK pre-flop, fold everything else) i came out of the tables up $3 after clearing. So i got $25 + $3 i made

So no u cannot sit out, but ur money doesnt have to have gone into the pot