Who told you that all Catholics must partake of all 7 sacraments? Not everyone gets married, does that bother you, too? Many do not receive the Annointing of the Sick (Last Rites) prior to dying. Does this trouble you as well?
Did Paul leave Titus in charge of the local church he established, or did he leave everyone there in charge. Check your Bible.
If one can make an act of contrition on their own when dying, why must you confess to a priest? Why can't you go straight to our LORD and SAVIOR JESUS CHRIST all the time?
Because ordinary times and extraordinary times are different. Sacramental confession serves many more purposes than just the granting of saving grace. When was the last time you sat down with a disinterested person and took an inventory of your spiritual faults? When did you last seek guidance in overcoming a difficult attachment to sin?
A different reason is for troubled things, really bad and evil things. Sometimes people are wracked with guilt about a deep dark sin. Hearing that one is absolved from another person can help greatly in healing the person from their own deep wounds.
How many Churches (Catholic and non) run programs, for example, to help women who regret having had abortions and feel guilt for their earlier action? This is all about reconciling the person to God's forgiveness and healing the harm.
SD