Interesting, that's exactly what I love about PC collecting. There was a phase of big box releases where basically every game felt like a Collector's Edition because of its inserts. Lore books to accompany the rule books, trinkets in the box, cloth maps, security wheels and more. And you can always discover new cool things inside other people's big boxes. Much communication was done via mail, so it's fun to find envelopes from the developer inside with patch disks or letters answering questions.
Console collecting is starting to get very nuanced too. Like getting the first print matte sticker black box game, or Mario 3 with "bros" on the left, non-NFR Sonic, Dr. Wright Megaman, orange lettered MTPO. Strangely, I have no desire to collect those even though I love collecting all of the extras for PC games.
Anyway, I understand where you are coming from, but just wanted to share what I love about collecting PC games.