The Curious Case of the '81 Box

I started sorting through the 5000 count box of 1981 Topps cards that I scored as part of my great $20 buck find. You can see how I acquired the loot here.
A very odd trend unfolded.
I started on the far left side of the box. About 1 1/2 rows in, I started seeing the same guys again and again, and in the same order.
Exhibit A;

Caudill, Goltz, Camp, Johnstone, Dempsey, Youngblood, and so on. There would be about 20 - 30 of the same card in a row. Oddly, these cards are not sequentially numbered. They're not organized by team either. I can't figure out what the original owner was doing with this.
Exibit B;

Of these five cards, one group was from row two, and the other was from row five. I could grab any random handful, from any row, and easily find the exact same grouping in another place in the box.

I have not looked at each and every card. After the collation anomaly, I just started looking for the same card groupings. I am going to do a more thorough search and checklist of what's here, but it looks like a ton of doubles. Of that first group with Caudill, there are probably six or seven more of the exact same groups spread around in the box.

Sadly, it looks like all the stars have been ganked from the box. A grouping of Rose, Carlton, Gibson, Brett, Yount, Reggie, and Yaz ain't happenin'.

Even with the mass quantities of doubles, I am still happy. These cards are in extremely excellent condition. They are not smokey or musty smelling. After I combine what I have previously with what's here, I will have a  "for trade" checklist ready.