Why SP's and DP's?

Why back in the late 40's and early 50's did card company's make certain cards SP's and DP's? Collecting cards were mainly for kids with no value attached to it so why the tough cards, ect..
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Comments
1) make folks buy more packs to complete sets.
2) card placement on sheets. If you've got 90 cards in a series, and a 110 card sheet, you get 20 DPs.
3) series issues. Kids scoop up the Series 1 stuff, and sales die die down through the year until the last series gets under-printed due to the lack of demand.
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though never personally participating in such said events, i have seen it on video back in the 80s.
julen
RIP GURU
<< <i>dp involves serious flexibility, ambition and a willingness to be a "freak".
though never personally participating in such said events, i have seen it on video back in the 80s.
julen >>
D's: 50P,49S,45D+S,43D,41S,40D,39D+S,38D+S,37D+S,36S,35D+S,all 16-34's
Q's: 52S,47S,46S,40S,39S,38S,37D+S,36D+S,35D,34D,32D+S
74T: 241,435,610,654 97 Finest silver: 115,135,139,145,310
73T:31,55,61,62,63,64,65,66,67,68,80,152,165,189,213,235,237,257,341,344,377,379,390,422,433,453,480,497,545,554,563,580,606,613,630
95 Ultra GM Sets: Golden Prospects,HR Kings,On-Base Leaders,Power Plus,RBI Kings,Rising Stars
<< <i>I thought Topps did 132 card sheets? >>
They did -- but I'm not sure when that started. There are some super size 264 size sheets, too, and I know that Bowman had different sheet sizes.
But 132 has been the standard for the last 25 years, if not longer.
"All evil needs to triumph is for good men to do nothing."
julen
tgif
RIP GURU
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Mark
Raw: Tony Gonzalez (low #'d cards, and especially 1/1's) and Steve Young.
<< <i>The 132 card sheets started when Topps increased the size of their sets to (the then standard) 792 cards. It made for a perfect 6 sheet run. 1982 I believe. >>
I'm pretty sure they go farther back, to either 1978 (when they started their four year run of 728 card sets, which required 66 DP's) or 1973, when they started a five year run of 660 card sets, which required five 132 card sheets.
D's: 50P,49S,45D+S,43D,41S,40D,39D+S,38D+S,37D+S,36S,35D+S,all 16-34's
Q's: 52S,47S,46S,40S,39S,38S,37D+S,36D+S,35D,34D,32D+S
74T: 241,435,610,654 97 Finest silver: 115,135,139,145,310
73T:31,55,61,62,63,64,65,66,67,68,80,152,165,189,213,235,237,257,341,344,377,379,390,422,433,453,480,497,545,554,563,580,606,613,630
95 Ultra GM Sets: Golden Prospects,HR Kings,On-Base Leaders,Power Plus,RBI Kings,Rising Stars