Hi,
You are touching an interesting point.
RW is relatively new software and much more niche than the Hero Lab and Army builder. It is universal campaign organizer which requires more effort to work with, to prepare in advance and is limited to GM audience mainly. This reduces the amount of possible contributors for free content, just as it is in the open-source world. Here your mileage may vary
If nobody messaged you about realm based on 5e SRD (it is the only portion of the license that can be freely used on the web without sentenced to death), check the FB group as well. I am 100% sure that someone out there has 5e srd in ready to share realm, but it is hiding in plain sight
On the licensing part - yes, you are not allowed to share or sell realms with content that is not free, open or licensed to you, but i doubt anyone can prevent you to share with other friends for personal use. It is the wet dream of every publisher everyone to buy their own books, no group sharing (especially the dead trees), but it will never happen, people are not dumb consumers (i hope). In fact, i hate so much the model where digital books = printed books (or close), that i either pirate or wait some grand sales. I always buy the printed books for systems i will play, but I don't find fair to pay three times for something I already own, especially when the effort for the digital products being close to none and restrictions more (DRM, effort to crack it so it does not bother you and etc).
I have Dark Heresy 2, since i am Warhammer 40k junkie.