Quite often a group of fields in a portal row or in list view are grouped together so that the user can simply click anywhere on the line and go to the related record. You can select one object and add a script then group them OR you can select them and group them and attach the script. Unfortunately it is difficult sometimes to determine which object that has the script and figure out which script and any script parameters that might be setup. If you are in a big hurry and break apart the group and you didn't figure out which script was attached to it you've thrown away the evidence of what the button was supposed to do and any script parameters as well.
I know you could attach the script to each individual object but then if you change scripts or parameters you have to do it on each one. Plus that doesn't cover any space between the fields.
It would be great, when breaking apart a group of objects with a script attached that at least one object retain the script. Might not be possible when attaching to a predefined group but if you have a script on one object then group the others it would be nice to protect that attached script. I've wasted several hours determining which script was attached (and then breaking apart script after script to determine which script parameter was being passed) when someone grouped an image/icon on top of a button and the layers are making it difficult to pinpoint the script.
Also speed up design if you are grouping several fields on a portal row then have to break it apart to change out fields.