1984 Topps "glossy send-in" Question

[TanksAndSpartans]

I'm working on this set today - these are cards I pulled from packs as a kid and I'm confused on something.....

There are 11 cards which I would call glossy ("Glossy Star Cards" or COMC calls them "Glossy Inserts"):

1 Curt Warner Seattle Seahawks
2 Eric Dickerson Los Angeles Rams
3 Dan Marino Miami Dolphins
4 Steve Bartkowski Atlanta Falcons
5 Todd Christensen Los Angeles Raiders
6 Roy Green St. Louis Cardinals
7 Charlie Brown Washington Redskins
8 Earnest Gray New York Giants
9 Mark Gastineau New York Jets
10 Fred Dean San Francisco 49ers
11 Lawrence Taylor New York Giants

Cards 1-3 from my binder shown below.

There is also a subset of cards:

1 MARCUS ALLEN
2 JOHN RIGGINS
3 WALTER PAYTON
4 TONY DORSETT
5 FRANCO HARRIS
6 CURT WARNER
7 ERIC DICKERSON
8 MIKE PRUITT
9 KEN ANDERSON
10 DAN FOUTS
11 TERRY BRADSHAW
12 JOE THEISMANN
13 JOE MONTANA
14 DANNY WHITE
15 KELLEN WINSLOW
16 WESLEY WALKER
17 DREW PEARSON
18 JAMES LOFTON
19 CRIS COLLINSWORTH
20 DWIGHT CLARK
21 MARK GASTINEAU
22 LAWRENCE TAYLOR
23 RANDY WHITE
24 ED TOO TALL JONES
25 JACK LAMBERT
26 FRED DEAN
27 JAN STENERUD
28 BRUCE HARPER
29 TODD CHRISTENSEN
30 GREG PRUITT

PSA and COMC are calling these (1-30 above) "glossy send-in", but I'm pretty sure I pulled them from packs without sending anything in and unlike the subset of 11, they aren't all that glossy to me.... Does anyone know why they are called "send-in"? Weren't they included in packs?

Here is a link: http://www.psacard.com/psasetregistr...te.aspx?c=2952

I included an image of one of my pages showing cards 2-8 from the subset of 30 below.

Finally, the set also has "super play game cards", but I'm not worried about these - just working on the main set and two subsets.

Thanks for any help!

P.S. If you just want to chime in on this set, feel free. One thing I noticed after putting all these into binders is that they sure have a lot of "tilt". Centering seems pretty tough.