I submit that none of these are “secret menu items”. They are lists of things to put on other things.
Well, except for the neopolitan shake, but McDonalds has let it be known that shake mixing is allowed and even promoted it with that ridiculous Chocolate/Shamrock drinking straw.
Most of these items are no more ‘secret’ than the fact that if you order french fries at Wendy’s, you can dip them in your frosty.
btw- the choc. mint shake is actually pretty good, at least as these sorts of things go.