It is to create awareness and outrage against the illegal and cruel blockade that Israel has put in place. This in turn would force Israel to choose between isolation and continueing the blockade.. Israel took the bait and fell into the trap perfectly. Look at how quickly Israel greatly expanded what is being allowed into Gaza.
Bennett, Deri expected to resign from Knesset, remain in cabinet under new 'Norwegian Law’ (Haaretz)
from the article: Libya-sponsored aid ship originally headed for Gaza enters Egypt port