Just like their RNG counterparts, some live casinos offer new players free bonuses with no deposit required. The purpose of these bonuses is so that you can try out their games without having to risk your own funds. Most no deposit bonuses are often followed up by generous deposit match bonuses.
Each live casinos no deposit bonus will be a little different, and there may be some game restrictions - eg: you can only play roulette. The bonus terms vary so make sure you read the rules before you start playing. If in doubt, ask customer support.