Gerardo -
As long as you don't violate the reference specs on startup/power-up (due to power transients), there isn't any reason that you can't do this.
However, the reference directly affects the performance of the device, so while you can do what you describe, you may not get the maximum performance from the datasheet. You would need to try it and see if it is acceptable. The concern would be noise added, drift of various components, and variation of components for mass production.