Not there for its own effect — it's there to help you absorb everything else.
Black pepper extract, standardized for piperine, doesn't get included for a vitality benefit of its own. Its job is entirely about improving how well your body absorbs the other ingredients around it.
Piperine has a reasonably well-documented track record for boosting the bioavailability of various nutrients and botanical compounds — essentially making sure less of the formula goes to waste.
In HoneyPower, black pepper extract is the sixth and final named ingredient, added specifically to help the other five actually get absorbed.