You may use "View All" function for various reasons :
If you have useful and unique content in Nuggets, it's a good practice to display them all in one page. This is crucial for SEO (Search Engine Optimization).
You may display all Nuggets from a specific Category, regardless of how many are they.
For indexing and thumbnailing purposes.
For View All display, you have less parameters to set.
Parameters of View All
First of all, you don't have to set Number of Slots, because a single slot behaviour is repeated. And you enter this in "Slot Behaviour for View All" block.
"Single Nugget" feature is disabled for obvious reasons. You can choose either "Full Random" or "Category Based". For the characteristics of these fields, you can refer to Standard Display. They remain the same. Also here, you have the option to choose an exception category.