We had some similar discussions in our company after starting with Holacracy (and haven't solved them yet). IMHO there is one question lying underneath: do employees benefit from company success (bonuses, shares) or are they just paid for their work effort?
When I benefit from lets say a dividend from the EBIT, I choose roles where I can help increase EBIT the most. I accept if I have to "carry more" by acting as Lead Link, Secretary or whatever, I just try to create the most value possible
If I have no stake from profit I would like to be compensated for my "extra work" or work that lies outside of what im hired for.
So far we failed to solve this issue with a systematical approach