Yes and No - to buying the datasets that are in HL. Because the APG and Bestiary are so massive and take so much time - fans haven't done the work for those products (and would likely not do so). Yes, even though the APG and Bestiary are done, a fan most certainly could decide that the $20/10 isn't worth it. But I seriously doubt it (and I've purchased the Bestiary dataset and don't think its worth it - not yet at least).
Here's why a fan will likely not do the APG/Bestiary - I did Seeker of Secrets and it's not like there are a whole lot of items, feats, spells or other things with it. But there is more than enough. It was massively time consuming. And trying to figure out the coding aspect. Heck, I think I even marked several of the items as something like 'could be incomplete and might not reflect correct bonuses'. ShadowChemosh does a lot of data sets - including several of the regional companions (Taldor/ Cheliax, etc...) and those he's offered as part of the OGL/PFSRD/PF Community Policy.
However, HeroLab/LoneWolf has stated that they will be doing these datasets and selling them. That doesn't mean that the work that I or ShadowChemosh or others will be invalidated - it just means that if you want to make sure the data set is correct (and be updated as needed) you need to pay for it. And ultimately, that's what you're doing when you buy the HL version - even for a computer programmers, it's a lot of work (and extra hard for someone like me who as to ask for help every 10min and then hope my questions are answered).
Now going back to the Bestiary. While I purchased it and I don't think its worthwhile - that is only because I've yet to use it. I attempted to understand that aspect of HL just over the past couple of days (see my post about advanced creature templates). Mathais gave me a couple of pointers as did others. I still didn't get what I wanted - but because the Bestiary is so massive, Mathais hasn't completed everything that he wants/it needs. Plus working on the APG and upcoming other data sets. To me, it seems like with the official aspect of Pathfinder - they have their hands full. But its certainly a worthwhile product as a whole, and even with no job for the past 2 years in a down economy (Vegas really sucks), I think I'll pick up whatever data set is next.
Be Well.
Theocrat Issak