I have an Office 365 subscription for my business email, so the extra cost to use these apps on my iPad was $5/month.
It's funny how people will line up to pay $600+ for an iPad Pro, and then complain about having to pay for software.
It kind of annoys me. I'm in the music industry, and it's the same thing there.... People will pay hundreds of dollars (or even thousands) for the best stereo equipment, but then they complain about having to pay a few dollars for music.
Even though you can't physically hold software or music in your hands, it's still a product that someone worked hard to create, and they are entitled to earn a living from having created it.
It seems that modern society is very respectful of intelectual property when it's in the form of patents for physical items you can hold in your hands, but much less so for copyrights. That is very unfortunate, and probably the reason why the biggest complaints about the iPad Pro are the lack of good software. Who would want to spend their time creating good software when nobody wants to pay for it?