Not legally, no.
About the only way you could get away with it is if, somehow, Blizzard simply forgot to charge you. This happened to a co-worker who was playing the original EQ. It seemed to be some kind of bug in his billing, the kind of thing that's probably more expensive to fix as compared to what revenue they'd be getting after fixing it. He played it for something like 4 years without ever getting charged.
But, the odds of that just happening are non-existant. Pony up the dough and enjoy your game. And also keep an eye open for the retail 60-day cards occasionally going on sale.