It absolutely matters. It would be foolish to not include it in your college application. It is prestigious and it does not matter if you get the scholarship money or not. Just like people who go to compete in Jeopardy don't do it for the money but for the prestige. People don't try for NMS for the monetary value but rather as a signaling device to colleges (and yes, there are a bunch of colleges that will give you a full ride and more with NMS, especially if you indicate that you are interested in a hot major like CS.
When you apply to college for the EA/ED round (in September or October), all you have is the results up to SemiFinalist or you are listed as a commended scholar only. To be considered a Finalist, you have to write an essay (that you can repurpose for common app), have a high proof SAT score, write a mini application and have your school also write recommendations etc. So the process of application to the NMS Finalist round itself is very helpful in getting you started on the rest of your college applications.
My kid is going to flagship in- state school. When he applied, he was only a Semifinalist. The college gave him a generous merit scholarship to sweeten the deal (well, keep in mind that for an in-state student, the costs are already low. So even getting $10 K a year from the college takes care of the tuition or dorm fee).
After the admission, he got the result from NMSC that he was a NMS finalist. At this point the state flagship school sponsored an NMS scholarship for him too and gave him 4K more. So that was in addition to his generous merit scholarship.
TL;DR version - yes, it is a prestigious achievement to add to your application. It does give your application a boost - BUT, NOTHING IS GURANTEED as far as admission to highly selective colleges are concerned because their criteria are not transparent at all. Legacy and race trumps NMS, 1600 SAT and 4.0 GPA.