|Charred and unburned staves|
There is another side of the story too, many of the rums have spent time in barrels before blending, and some are rebarreled after blending to marry the flavors creating a new and different characteristic again. This will generate a completely different rum that just blending and bottling the rums can not.
How come a bottle of old rum is so much more expensive than a young rum? The most expensive portion of making rum is the aging. The rum from the distillery has 2 to 30 years of aging before the bottle can be sold. This means that huge amounts of rum are sitting in storage for many years before they can be bottled and sold. Think about if you could not reap the benefits of your labor for that long and you had to have enough space to store it as well. This is expensive any way you look at it.
The next time that you open a bottle of twelve to fifteen year old rum, just think about where this nectar has been and what the barrels have done for it in the time since it was distilled. It is truly a magical change. It is the natural and slow way of getting a rum flavor, and the best rums are done this way. ;o)