People with any interest in testing these betas should also be smart enough to make a google search and download the beta without paying... it's not that hard. Basically it won't make much of a difference, because the majority of apple users doesn't even know a beta exists and if you told them, they wouldn't care.
Hmm, well I am an active user and I don't mind getting apps via torrents, but an OS from a less trustwurthy place has scared me off till now.
If it all would be supported by Apple wouldn't more people particpate?