Sorry, but speaking as a Hoop veteran for decades...
You are not required to stand in line for 30 minutes.
You can find a spot to sit and watch for the doors to open,
(they ring a very large "dinner bell") and just wait for the crowd to thin down as they enter the theater.
You will not get a "worse" seat if you enter later as ALL SEATS ARE ASSIGNED IN ADVANCE when you make your reservation.
It is not first-come, first served.
In fact, when you pick up your Will Call Hoop ticket (you can do so at any Guest Relations on WDW property, including any WDW Resort concierge desk) your table number will be printed right on your ticket.
If you forget to pick up your Will Call ticket in advance, you can do so when you arrive at the Hoop location (Pioneer Hall) at a Concierge/Will Call window to the left of the theater building, adjoining the restroom area.