Adobe didn't create it originally, just for your info. It was started by Macromedia, and the whole idea was to provide some protection by it hiding in the swf, but that in order to have better development capabilities for others it had to be openable. Just like you spend a long time working on an HTML/CSS layout it can be swiped and copied, its because the code HAS TO BE AVAILABLE for the end user in order to be processed. Its not that they couldn't do more, but that its not why it was created.
I see you are really concerned about theft, but really the best solution is to follow the open source model, which encourages people to improve rather than to just steal. I'm sorry, but if you need a secure platform you will have to do something that doesn't download the script/files to the user, which means you will ultimately make it practically unusable. You'd have to make a compiled program, which still can be reversed engineered. There is NO WAY to make it 100% safe. The best you can do is deter them by making the code unreadable and putting a notice on your site.
Also, assess what you are doing. Are you really a big target? I haven't considered anything I have done to be worthy of theft, they are all really specific tasks that have little value to a hacker.
jeremy - gnomeontherun
Educated questions often get educated answers, and simple questions often get simple answers.