I'm always amused by the assertions that "Apple wants to control..." this and that because they are always based on a misunderstanding.
iPhoto offer your 15 or so ways to access your photos. iPhoto has more ways of accessing your Photos that any other app I know of, including Aperture. It has far more than Picasa, for instance - being that your Photos in iPhoto are available in every Open... dialogue in the entire Operating System.
Your "issue" is based on a simple misunderstanding: You're confusing your Photos with the Files that contain them. You want access to the files. You don't need access to the files. You need access to the Photos.
The illustration I use is as follows: In my iTunes Library I have a file called 'Let_it_Be_The_Beatles.mp3'. So what is that, exactly? It's not the song. The Beatles never wrote an mp3. They wrote a tune and lyrics. They recorded it and a copy of that recording is stored in the mp3 file. So the file is just a container for the recording. That container is designed in a specific way attuned to the characteristics and requirements of the data. Hence, mp3.
Similarly, that Jpeg is not your photo, it's a container designed to hold that kind of data. iPhoto is all about the data and not about the container. So, regardless of where you choose to store the file, iPhoto will manage the photo, edit the photo, add metadata to the Photo but never touch the file. If you choose to export - unless you specifically choose to export the original - iPhoto will export the Photo into a new container - a new file containing the photo.
So why do you need to access the specific files?
And if you really have a jones for file management, why not run a Referenced Library?
You don't need a "workaround". All you need is to do is
1. Understand iPhoto - which means understanding the difference between the data and the file that contans them. The data is far more available, and in far more ways, with iPhoto than with any other app you can find.
Or, if you really want to see the the jpeg files in the Finder:
2. run a Referenced library. There are good reasons not to, and it offers zero additional functionality and possible pitfalls further down the road, but you'll be able to visit with your files if you want to
Or
3. Use another app. It's really simple. If the app won't import from your Phone or iPad then use Image Capture (in your Applications Folder) to get the files from the device and then do what you will. (But if you're using Picasa read the licence carefully and be sure your happy with hundreds (and hundreds) of hidden files scattered all over your Hard Disk.
iPhoto is a Photo Manager and not a file manager. It's not about "control" or anything like it. It's about using a database to manage data not containers.
Regards
TD