When I purchased my Renegade, I only had the option of 4x4, mainly because I live in Massachusetts and I really need it in our often harsh winters. But, I also plan on occaisionally taking my Renegade on trails of some sort, so I wanted the 4x4. If you feel that you do not need the 4x4, I would say don't buy it. If you don't plan on going offroad, and are fairly confident in your snow driving abilities, then you may not need to spend the extra.
But, my thought process is also that I refuse to buy a Jeep without 4x4. For me, it's one of the main reasons for buying one.