A few interesting ideas spring up when you think about this. For example, if Laban was drunk following a celebration of the Passover feast, it would tie in to the death of the firstborn sons in Egypt. Bradley explains:
As we have seen, the story recounted in 1 Nephi implicitly connects Laban to both Joseph and Egypt by his inheriting the Egyptian brass plates as a descendant of Joseph of Egypt. Laban thus plays a dual role in the story as both Jew and Egyptian.
Likewise, Lehi’s exodus has the dual role of recreating yet reversing the ancient exodus, in both particular and thematic elements. The dual passing-overs that are celebrated during the holiday give parallel significance to the sequence of Lehi’s sacrifice (possibly the Passover lamb) followed several days later by Nephi comparing Laban to the Egyptians at the Red Sea and then, later that night, slaying him.
Laban’s connection with the Passover in this instance would have extended beyond it merely being an occasion for community socializing and drinking. Laban died at Passover, and this echoes the original, biblical Passover under Moses, when God destroyed those who tried to oppose his people. Laban had been celebrating with the Jerusalem elders, wearing full military dress and carrying a finely crafted sword. In the commandment in the Book of Exodus instituting the celebration of Passover, observance of the feast includes two ceremonial occasions or “holy convocations” (Ex. 12:16). One was on the first day of Passover, related to death passing over Israel’s children and landing instead on the Egyptians’ firstborn, the other was on the festival’s final day, related to passing over the Red Sea and the destruction of the Egyptians. If Lehi’s sacrifice before sending his sons for the plates was a Passover observance accompanying the first convocation, commemorating the deliverance of the Israelites’ firstborn, then the occasion of Laban celebrating with the elders would have been the final convocation, commemorating the Israelites’ deliverance at the Red Sea and the Egyptians’ destruction.
Lehi is leaving what was Moses' promised land to seek a new promised land. In doing so, "the law" must be obtained (presumably from the eldest son of a line of eldest sons of a lineage of Joseph). Laban died as a result.
Bradley argues that Laban's death mirrors the drowning of Pharoah's armies in the Red Sea. This is presaged by Nephi in his words to his brothers:
2 Therefore let us go up; let us be strong like unto Moses; for he truly spake unto the waters of the Red Sea and they divided hither and thither, and our fathers came through, out of captivity, on dry ground, and the armies of Pharaoh did follow and were drowned in the waters of the Red Sea.
3 Now behold ye know that this is true; and ye also know that an angel hath spoken unto you; wherefore can ye doubt? Let us go up; the Lord is able to deliver us, even as our fathers, and to destroy Laban, even as the Egyptians. (1 Nephi 4)
I find this beautiful and deep. There's layers to this text.