Is a wedding decor a MUST?

I would like to share some of the info which i saw while surfing the internet.

The reasons for decoration

1) To increase the ambiance mood - create the romantic feeling
2) To follow the theme wedding - A great mix of floral, static, lighting, fabric, etc
3) To make an impact to your guests so that they remember your wedding.
4) To enhance the venue, so that your photographers have a great background and foreground to capture beautiful and romantic moments.
5) You have some budget for it. Budgeting is important so that you know which area you are spending specifically.
6)etc,etc! :) Many of you would have your reasons not listen above.