In any case, when javascript code is copied, it only means good things for internet-users, since the performance of the web is enhanced. A good example is a search engines. If this javascript had a patent on it, imagine how difficult it would be to use the internet. I won't say that allowing javascript to be copied will have the same results as open-source software, but I will say that it might follow the same concept. That being, the program is copied from original author by a new user.
New user makes modifications.
Then another user copies the program, and makes new modifications and improves the program. The idea is if the trend continues, each time the program is copied, a better program is produced. As students of JavaScript, it's really useful to be able to look at how people are doing things, even if we can't always understand them. In general, it's nice to be able to see the nuts and bolts of how something's created. But generally, it seems that people who enjoy working with computers often also like to innovate and rarely take one way of doing things as gospel, so perhaps that wouldn't be much of a problem.