I inspect mainly newer homes and of course they all have trap primers going into the basement floor. Sometimes the small primer lines go into the floor quite a distance from the floor drain. Usually they are beside a stack.
If the purpose of the trap primer is to keep the floor drain trap full, wouldn’t they have to enter right at the floor drain. Obviously they are not there to keep the floor drain trap primed so I’m confused.
All I have seen you can hear the water trickling into the trap,
…Cookie
Here is an illistration for you.
http://www.zurn.com/operations/specdrain/pdfs/installation/t1.pdf
Hope this helps.
Marcel 
The line and priming device should be there to prime the P-trap serving the floor drain. Where the line enters the floor should not be a problem as long as it ends up supplying water above the P-trap and remains functional.
The priming line is a very short distance from the top (usually in a tapped inlet). You can take the top off the drain and see it to confirm. If you really need to, you can shut the water off (normally) to the primer and check to see if it stops running in the drain.
Thanks guys.