Paul Lukas from the always great Uni Watch has solved the mystery of the pocket schedules and offers proof of their existence:

Uni Watch should be part of your daily rounds if you at all like the stuff I do over here. Mets Police is a mix of Uni Watch, Straight Cash Homey, Mushnick and the crap I have been emailing my friends about for years. Throw that in a blender and here we are…
As for the pocket schedules, read Paul’s article to find out how the legend of no-schedules started. You won’t believe the source.
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On a similar note, over the years I have given the Mets major grief about the design of the upper deck. Well kids, take a look at this…

Awful right? What a horrible obstructed view.
One thing….look again…I took that photo in San Francisco.
It must be a function of the geometry of the park 😉