Can I remove the finger inserts in scissors?

Most scissors come with removeable finger inserts, usually made of rubber or plastic. You don't need to use them, however they are designed to cushion your fingers, to reduce hand strain, and provide a better fit for thinner or smaller fingers. Most scissor inserts are removeable, but the scissor description will usually tell you if they are or not. 

Is it better to use the finger inserts?

Finger holes in grooming scissors are generally "one size fits all" however, different people have different sized hands. Finger inserts can help to reduce the size of the finger holes, and add extra padding and support, to ensure your fingers are comfortably and correctly secured within the finger holes. When held correctly, only the top of your ring finger and thumb should be in the finger rings of your scissors, and only your thumb should move when cutting. Using the finger inserts can make it easier to maintain the correct finger positioning, as they prevent your thumb from sliding too far into the thumb hole. You will have the most control and produce the best results when your scissors are held and used correctly.