Talk:Tin of Sardines/@comment-71.185.231.36-20190517011836/@comment-72.195.236.172-20190820073330
I think it is part the "gross" factor of canned whole fish and/or an attempt to balance what would otherwise be an all around nearly ideal food item (fairly lightweight, but dense in calories, quenches thirst, no tool needed, etc).
I don't know that canned sardines are more likely to cause food poisoning in real life compared to most other canned goods.