Garmin cannot obey each person's first day of week setting and still show data that is consistent for all participants.
For example, consider that your first day of week is set to Monday and mine is set to Sunday. If, on Sunday evening, I complete an activity that puts me ahead for the week. By my stats, I 'won' that week. But since your stats roll over the next day, you are free to overtake my stats for a week that my activities are no longer counting toward.
