This is an interesting post. The thought of "taking profits" also crossed my mind some time back and I also had a long thought about it because I wanted to do it in a sustainable manner, i.e. I still wanted to continue building my Hive account.
I also read a post on Hive, where one user had this 90%/10% rule, keep 90% and take out 10%. So that's one way.
In the end, I settled on just "taking profits" on the HBD interest so it would just be the 20% APR. This ensures that my principal Hive and HBD both remain untouched and will continue to grow. It wasn't any rocket science equation, I just feel that was something reasonable to "take out" to reward myself with coffee while I write posts in cafes. I guess you could say it's more symbolic for me, rather than needing the money for my daily needs, so my case is a fortunate one.
I don't have any issues for those people who wish to take all out actually. It's their choice. In fact, if their Hive earnings can make a positive impact in their lives, it is a testament of how meaningful crypto/Hive as a platform is.
That's not a bad strategy and I know a few others who do the same with the interest from HBD in savings. If it buys a coffee or two in the real world then fair enough.