Section access table is actually loaded into memory but hidden from users, which makes a lot of sense in terms of security: the table stores not only usernames but passwords and so.
But you can anyway load the same table you load in section access anywhere in the script, but renaming the fields to avoid concatenation. Note that in QlikView all tables are available to all users, but you can use the OMIT field to prevent users without privileges to see the fields that correspond with those from the renamed section access. So you have your section access as usual, but you load too the same table in some other part in the script.
Hope that helps.