Question : Why should 1:1 Relationships be used for Entities with Subsclasses?

Why should attributes that are specific to distinct subsets of an entity be separated out into separate tables with 1:1 links to the main entity table?
For example, a superstore that sells everything from soup to lawnmower nuts, has a main Products table (atributes: Brand, UPC) and separate tables for sporting goods products (attributes: Sport, Season) and food products (attributes: ShelfLife, DiabeticFriendly). This may appeal to one's sense of data organization, but creates some overhead (must manage multiple tables) and some restrictions (there is no way to implement bilateral RI in MS Access). Are there any other pros and cons? Assume that ULS is not used or required.

I've googled some links in favour:
•      http://onlamp.com/pub/a/onlamp/2001/03/20/aboutSQL.html
•      http://msdn.microsoft.com/en-us/library/dd326769(VS.85).aspx

and others against:

•      http://www.sum-it.nl/cursus/dbdesign/english/intro030.php3
•      http://msdn.microsoft.com/en-us/library/4s9x13w7.aspx
•      http://www.docstoc.com/docs/4193380/Relational-Database-Relationship-Types

Answer : Why should 1:1 Relationships be used for Entities with Subsclasses?

This has the steps if your using sql server 2008...

http://www.mssqltips.com/tip.asp?tip=1709