[pct-l] Why do they have Media mail?

[AsABat]

I was curious why they even have media mail. I learned media mail was
created in 1938 to provide lower postage for books to "encourage the flow of
educational materials through the mail" to promote "educational, cultural,
scientific, and informational values." Consider in 1938 there was no
internet and lots more remote homes. In 1984 they added some computer media
(CDs, etc.), but not video games and USB drives and such. (
http://pe.usps.com/text/CSR/PS-334.htm)

In the course of looking this up I also found reference to packages being
opened to verify it qualified and then closed and rubber stamped that it was
opened by the USPS. I then recalled having seen this on some packages I have
received. So yes, sometimes they do check. (
http://www.paperbackswap.com/forum/topic.php?t=173268)

IF the postal service is losing money as they say, and if the work (labor
and fuel) to move a pound of something is the same whether books or not, I
would suspect that media mail might even be a money loser for the post
office.

AsABat