The consequence for not attending the memorial is DEATH...
Therefore, anyone deliberately staying away from this celebration, on March 29, does well to consider this question: If willful disregard of the ancient Passover was punishable by death, would not a more severe punishment be meted out to one who spurns the Lord’s Evening Meal, trampling on the provision represented by the bread and wine? Surely you will want to accept the invitation to be present for this celebration and, in faith, accept the provision of Jesus’ ransom sacrifice.—Num. 9:13; Heb. 10:26-31. –Watchtower March 15, 1972 page 167