Three reasons:

1) The code does not just generate the checksum, but also the whole line you need to use.

2) This way it uses the exact same code as is used inside InstaUp2Date, so there is never any doubt that both will get the same result for a given file/directory.

3) For directories (not used so much right now, but they might make a comeback) I was not entirely sure that I wanted to checksum everything, so this allowed me to exclude things (like documentation). This code never actually got written. And directories were primary on my mind for #2.