Restoring your belongings saves you money in the event of a fire loss.
Why? If you have an actual cash value policy, which is the most common, you will be compensated only for the current value of "total loss" items.
So while you may have paid $25 for some simple shelves 15 years ago, with depreciation your insurance payout won't be enough to replace those simple shelves. Restoring them, they are returned to you in a "preloss" condition, and you still have those simple serviceable shelves.
Restoration is clearly a better choice compared to Replacing.