relation between small tablefooter height and empty rows

relation between small tablefooter height and empty rows

I have a question regarding the relation between a table footer and the
number of empty rows that are displayed. Lets assume that we are using
UITableViewStylePlain table view. And the number of rows that are returned
is 2. Then by default, iOS inserts empty rows in the table. If I want to
remove those empty rows, then I only need to return 0.0f (or some very low
value) in heightForFooterInSection method (and sometimes also return empty
view in viewForFooterInSection).
However, A footer is something which is added at the end of the section.
The diagram given in the following link also confirms that.
https://developer.apple.com/library/ios/documentation/userexperience/conceptual/tableview_iphone/TableViewStyles/TableViewCharacteristics.html#//apple_ref/doc/uid/TP40007451-CH3-SW4
Then, how does making a footer extremely small help in removing empty rows
? Shouldn't we make the footer extremely large so that it occupies the
whole screen ?