Since we're building one-world-tree rather than a multitude of individual trees, it's imperitive that we try to avoid duplicates. In order to accomplish this goal, and considering how many Joseph Smiths there have been through the years, it was found to be absolutely critical that there be at least some idea of a date (and preferably a geographic area) attached to every new profile. Even if you don't know the exact date, you can plug in a ball park guesstimate based on some even in that persons life...like if they were married in 1805 they were likely born within 10 years of 1785... then notate it as such in the biography so that future cousins will be able to see that this is actually their ancestor and add the information they know about them rather than creating a new duplicate profile. So you see in the long run, this requirement is actually in your favor, since it drives the collaborative nature of the WikiTree-experience.
Keep up the good work! We'll get this tree straightened out together!