'Come in' versus 'Come on in'


Could you please tell me the difference between the following sentences? If there is no difference, why waste energy on an extra ‘on’? And time and ink for that matter?

[b]1- Come in.
2- Com on in.

3- Come out.
4- Come on out.

5- Come back.
6- Come on back.[/b]

7- Come over please.
8 -Come on over please.


You sound as though you’ve already made up your mind that there is no difference, Tom. :wink:

Saying “Come on in” definitely sounds friendlier and also more encouraging than than “Come in”

I’d say the added degree of friendliness and/or encouragement would also present in your other sentences should they be used.