I'm surprised this is still an issue - though I guess not as surprised as I'd hoped to be. It's rather sad that there are still people out there who demand to be credited for work they haven't done.
Some journals have clear guidance for what merits authorship. For example, pretty much all medical journals sign up to guidance from the International Committee of Medical Journal Editors (http://www.icmje.org/recommendations/browse/roles-and-responsibilities/defining-the-role-of-authors-and-contributors.html#two) which requires
(So in the example above, getting the grant money would probably count as contributions to conception or design, so warrant authorship as long as the putative author then didn't abandon the project but could meet the other three criteria; but providing space for the work e.g. in a lab or recruiting participants, on it's own wouldn't be enough)
Most journals then require a statement of what the authors did to meet these requirements which is published with the article - so in order for someone who doesn't warrant authorship to claim it they, and their 'co-authors' have to lie in print.
So in the unlikely event my head of department, or anyone else, insisted on being added as an author when I thought they didn't warrant it, I'd ask them to justify the request using the ICMJE criteria.
Of course - thats the easy bit.
If you're working in an area which doesn't work like this, you have to think about keeping on board with the community. If someone senior really thinks they deserve authorship on your paper, and you don't, you have to decide whether you're going to keep them happy.
I'd suggest you may need to find someone else to persuade them they should't be named. That may be someone superior to them in your institution, or you may need to discuss with the editor of the journal you're submitting to - who can then ask for justification of contributions should they see fit.
Fundamentally though it seems that attitudes like this may suggest something rotten in the culture of either a department, or possibly a discipline. And culture change like this will take years.