Are you really sure that it will start the entire wallet from the beginning in case of any issues ?I think even while running a full node it will resume from the point where it stopped the next time you start it.
Yes there are many such cases possible. Sometimes your wallet's blkindex.dat might be malfunctioning. In this case you'll have to delete all your files from your 'roaming' folder and re-index your wallet from the beginning.
Also think of a situation where your computer crashes for some other reason and you have to format or change your hard drive.
In all these cases it will be easier to have a bootstrap file ready so that you can just import the chain offline and just re-index a week's chain which wend ahead at that time. It will save your bandwidth too.
If you want to be prepared, make regular backups of the entire folder. A bootstrap.dat would not be verified, copied the folder includes all verified data (and your wallet.dat).
So far I only am backing up my wallet.dat. What do mean by the entire folder? That folder in the roaming section?
But I am talking about a single bootstrap file in general which can be created and can be used by anyone (does not need any verification as such).