No one here can make the decision for you. The rule is NO, you are not supposed to do it. The reality is that YES, a few beers or a bottle or two of booze will most likely be "overlooked" by security. Just be prepared to write off the total cost if they do decide to make an issue of it.
And remember that this is only valid at the embarkation port. The ship's security people are quite strict at all the ports you stop at and if you bring something back with you they will take and hold all booze until the last day of the cruise.