jerejigga, you are absolutely correct, I just reread the documentation and saw that this permission on adroid is only necessary for saving to the photoalbum. I did not read all of the text the first time and figured that this is a must have for screenshots on android.
Thats Great news! 
About the App size, my problem is actually mostly for Android, as any naked Corona Android App already wieghts ~7mb, even if it is only a hello world app. So adding some highres images and audio pumps the App very fast up to 15 mb, what I consider quite a lot, at least for my App that has almost nothing in it… Anyway, if you think it is not that much of a problem, I will stop worrying about it. I thought I read about this somewhere here iin the forums (that it is bad to have a big apk file), but maybe this is outdated now…
@nick_sherman, hahaha, yah, it was already late when I wrote this post 
(And it really was accidentally
Are these lines real?
Best,
Felix