No, I wouldn't ask for it to be deleted, but I would always want reviews to be accurate; the join is definitely above their waists. The premise of the film is indeed quite stupid. (The non-identicality can be interpreted as being tongue in cheek, but the idea that they couldn't be separated because one of them has more of the liver is ridiculous - it is not a complex organ and could still be split equally.) However, I don't think that makes a difference with regard to accuracy of reviews. But yes, you're right that they would share buns out of a pack, so it would count in a non-pun sense.
This was coming coming on a few minutes ago so I watched the beginning. They actually DO share buns from a pack as they own the restaurant and cook the sandwiches as a team, working in tandem to finish each sandwich. But I didn't watch the rest of it. Too silly!