Aperture and iPhoto: How to make a copy?

Hello.

I'm on a MacBook Air - 2014 model, with OS X 10.11 installed.

(I decided to perform a clean installation, so, naturally, I erased all the info I add stored on it: such as Aperture & iPhoto apps, which were discontinued by Apple).

Now that I have my MacBook Air 'up and running' I know that I can install Aperture & iPhoto Apps again, just by going to the Purchase option on the Mac App Store.

But, I would like to know one thing: is it possible to make a copy of both apps to an SD or USB drive? I mean, let's suppose that someday those apps are completely removed from Mac App Store (which, apparently, happened for several hours recently) and for some reason I feel I would like to installed them again on this Mac or one of my older Macs, is it possible to create a copy of them (for example, whenever I download a new version of OS X, I always make an USB or SD bootable from it). Can I do the same with Aperture & iPhoto?

If not, what other possibilities do I have?

Thanks in advance for any information you may provide me with.

Kind regards.