Certainly, though, all-terrain shoes work fine. You can add a toe clip to a pedal for a little more control, as that will give your toes something to butt up against. There are also several pedal straps that release and engage easily, give you some of the control of a clipless pedal, and cost much less than clipless pedals. Eko's Power Grip, for instance, sells for $35 with a kit that includes pedals (www.ekosport.com).
But, I generally think clipless pedals are much, much better. Time's ATAC Alium is a light, dependable pedal that sheds mud well, re-engages quickly, and sells for $90 a pair (www.timesportusa.com). Many riders love the design of the Crank Brothers Egg Beater (www.crankbrothers.com), a pedal that actually gives you four clip-in points, not two. Some of the older models are popping up on sale for well under $100. Finally, there's the Ritchey Pro Logic ATB, a good-quality pedal you can find on sale for $50 per pair (www.ritcheylogic.com).