iTunes App Update -> ipa in Trash

Hi,
so here's the deal.
I searched the forum but didn't find anything related to "trash"
So you all know if you update your Apps in iTunes or sync the updates back from your iOS Device the Apps stored in your iTunes Library are put into the trash.
I'm digging for a way to move them into a directory on my drobo where I can keep them for histories sake
or just because sometimes the updates are actually downgrades in terms of usability whatsoever.
It turns out that you actually can't set a rule on a hidden folder.
And I understand why that is due to the crucial files in / till /~
But anyhow I just desperately need this rule :/
Have you guys any ideas or tips how to monitor the Mac OS Trash?
Thanks
so here's the deal.
I searched the forum but didn't find anything related to "trash"
So you all know if you update your Apps in iTunes or sync the updates back from your iOS Device the Apps stored in your iTunes Library are put into the trash.
I'm digging for a way to move them into a directory on my drobo where I can keep them for histories sake

It turns out that you actually can't set a rule on a hidden folder.
And I understand why that is due to the crucial files in / till /~
But anyhow I just desperately need this rule :/
Have you guys any ideas or tips how to monitor the Mac OS Trash?
Thanks