Come on, m8.
The "razor blade" thing is just some shit some random kids asked Oda on a SBS and instead of Oda saying "nah, it's just your imagination" he took the opportunity to make a joke about zoro and sanji rivalry.
Dude knows everyone's favorite food, he never makes "bad food" for any of them, despite the "i use the fresh ingredients for nami and robin only".
Even a fucking filler captures his essence better than some dumb SBS joke when he makes a freaking nutritional feast using only leftovers.
Stop taking these jokes for granted. One Piece is full of these stuff.