Is it normal for PhD students to do much "non research" work?
These all sound to me like usual activities for a PhD student (the "news articles and marketing material" bit sounds a bit odd to me, but that might be more field-dependent).

PhD programs are not typically designed only to allow you to do research, they are designed to teach you to do research, and furthermore to train you to be an independent researcher. That can include learning about all the other baggage that comes with research, such as finding funding, disseminating the research to the academic and sometimes lay community, mentoring junior researchers, etc. 

However, like most things, balance is important. It's hard to specify some number of hours per week or something like that for you to contribute to these "other" activities, but the most important thing is that you are able to make progress in your research.

Since your advisor will be the person judging your satisfactory progress as well as being the person assigning you all these tasks, you should have regular conversations with them as a student regarding this balance. Have these conversations early and as often as necessary. It would be appropriate to approach this question directly as you have asked it here, too: tell your advisor "I am worried too much of my time is being spent on X/Y/Z and it will be difficult for me to make progress towards my thesis."