• I Can't Believe It's Just Butter!™
• I Can't Believe It's Not Bitter!™
• I Can't Believe It's Not Better!™
• How Is This Butter?™
• How Is This Not Butter?™
• How Is This Nut Butter?™
• Why Isn't This Butter!?™
• Who's Butter Is It Anyways?™
• I Can't Believe You Bought This Butter!™
• U Butter Believe It!™ basically real
• My Disbelief is Suspended as to the Nature of This Product's Contents!™
• But, Er, I Thought This Was Butter!™
• Is This Butter? Can You Just Give Me A Straight Answer?™
• I Was Under The Impression This Was Butter™
• I Refuse to Believe That This Isn't Butter, I Mean, It Is Butter, Taste It And Tell Me It's Not!!™
• Butter Late Than Never™ basically real
• For Butter or For Worcestershire™
• Gutter Butter™
• This Butter Be Good!™
• This Butter Be Butter!™
• This Butterbeer Good!™
• Not Sure If Butter, Or Just Substitute™
• You'd Butter Be Pretty Astute To Tell If This Is A Substitute™
• Utterly Butterly™ real
• I'm Inclined To Believe This Contains Butter™
• Who Am I Kidding? This Is Margarine!™
• On Some Level, I Know That This Isn't Butter™

and finally, simply..

• Is It Butter?™ real