They're fascists, they always have an excuse. They can and did attack them under the excuse of the blockade.

there was one in 2010 where the bomb and killed people

Six civilian ships of the Gaza Freedom Flotilla were raided by Israel on 31 May 2010 in international waters in the Mediterranean Sea. Nine of the flotilla passengers were killed during the raid, with thirty wounded (including one who later died of his wounds).[1][2] Ten Israeli soldiers were wounded, one seriously. The exact sequence of events is contested, in part due to the IDF's confiscation of the passengers' photographic evidence.[3] The flotilla, organized by the Free Gaza Movement and the Turkish Foundation for Human Rights and Freedoms and Humanitarian Relief (İHH), was carrying humanitarian aid and construction materials, intending to break the Israeli naval blockade of the Gaza Strip.

So then don't carry flour and rice, go with pemmican or something similar, high protein, high caloric, high density food.

A brick of pemmican is better than nothing, which is what they currently have.