Commercial javascript libraries have a tough stance. "Free for non-commercial" is essentially meaningless, since there is no clear definition of commercial use. For me, I wouldn't even consider including such a library into any software (OS or commercial) which runs on multiple domains/servers/computers, because it makes licensing and scaling less flexible.
To justify a licensing price, a javascript library needs to offer huge, peerless, hard to imitate functionality, stable code base, rapid bug-fixing and preferably a paid team working on it.
Which isn't to say that nobody will buy it. At $99 per site even one or two dozens of customers would cover the development costs.