Doesn't matter how well known he might or might not have been (Kurland was actually training for the Academy Entrance Exam). According to onscreen dialogue, he still entered the shuttlebay without authorization. A case could be made that the only time Kurland was supposed to be in the shuttlebay was during his scheduled training.
Some quotes from the episode:
Coming of Age said:REMMICK: Very original, Captain. But how did that child acquire access to a shuttlecraft?
RIKER: Kurland is a highly qualified Enterprise Academy candidate, fully trained in many areas including shuttles.
...that really doesn't answer the Inspector General's question, Will. I hope someone, other than Jake, got in trouble for that incident. But we also learn this tidbit earlier:
Coming of Age said:TASHA: Captain, there's an unauthorized entry in main Shuttlebay.
REMMICK: Unauthorized?
PICARD: Who is it, Lieutenant?
TASHA: Computer reads the ID number of Jake Kurland. Bridge to main Shuttlebay. Mister Kurland, this is Lieutenant Yar. Respond.
REMMICK: Isn't the area secured?
RIKER: Not now, Remmick. He's going to take this out, Captain.
TASHA: I'm locking off the bay launch doors, Captain.
WORF: Too late. He's using the flight emergency override.
LA FORGE: Smart kid.
REMMICK: Kid?
TASHA: He's launching.
So, I'd gather that Jake had a dedicated ID number that gave him complete access to the shuttlebay and was also taught how to use the "flight emergency override." Possibly as a fully-trained backup, civilian pilot in case of emergencies.
In my head, Jake used his ID to gain access to his shuttlecraft, maybe non-chalantly whistling past the shuttle officers with an excuse of "Oh, I'm just checking out the Copernicus for my scheduled training course tomorrow." Then once, inside his shuttle, he activated the flight emergency override, which allows him to cut-off bridge access to the main shuttlebay doors (this may also be the point where the ship or a shuttle officer recorded the unauthorized entry).
I could see that override being necessary in an emergency if hostile forces have commandeered the ship/shuttlebay, or if some computer malfunction have messed with the bridge/shuttlebay controls (but not with the override controls).