Loved that scene, eoe. Loved Gregory Hines in that movie.
I'm pretty sure (with Google's help) that this is how it went, but correct me if I'm wrong:
In "Hair", we see Treat Williams' before and after his buddy cuts his hair. No barber or barbershop. And none of the other characters got a haircut.
In "An Officer and a Gentleman", we see the guys waiting in line to get their hair cut, but we don't see the barber cutting their hair. We just see the results.
In "Full Metal Jacket", there's a scene where we see the Marines get their heads shaved from start to finish.
I don't know about Biloxi Blues. I saw it, but I can't remember.
So at this time, I'll recap with "Full Metal Jacket" added:
B = Beauty Salon and Barber Shop scenes
1. Steel Magnolias
2. Barbershop
3. Beauty Shop
4. Soul Food
5. Poetic Justice
6 Married to the Mob
7. Shampoo
8. One Fine Day
9. Oceans Twelve
10. Moonstruck
11. Coming to America
12. The Shootist
13. The Godfather
14. Grease (Beauty School Dropout)
15. Legally Blonde
16. GI Jane
17. Runaway Bride
18 Five Car Stud
19. What's Love Got To Do With It
20. The Man Who Wasn't There
21. Memoirs of a Geisha
22. Le Marie de la Coiffeuse (1990, The Hairdresser's Husband), protagonist marries hairdresser
23. Fatou la Malienne (2001), protagonist is hairdresser
24. Fatou l'Espoir (2003), protagonist is hairdresser
25. De Vierde Man (1983, The Fourth Man), Renée Soutendijk owns beauty salon
26. Il Mio nome è Nessuno (1973, My Name is Nobody), Terence Hill gets a shave
27. Edward Scissorhands (1990), Johnny Depp is almost raped in a beauty salon
28. Kort Amerikaans (1979, Crew Cut), protagonist hates haircuts but is forced
29. The Crying Game (1992), Dill is a hairdresser
30. Italiensk for begyndere (2000, Italian for Beginners), one of the characters is a hairdresser
31. Say It Isn't So (2001), love interest is clumsy hairdresser
32. The Great Dictator (Charlie Chaplin is a barber in the Ghetto)
33. Giant
34. Hands Across the Table (Carole Lombard's character is a manicurist in a barbershop
35. The Women (Crawford, Shearer, Russell, Goddard)
36. Sweeney Todd: The Demon Barber Of Fleet Street (1936 British film)
37. Waiting to Exhale - Loretta Devine's character runs a salon
38. Pleasantville - barber shop scenes
39 Full Metal Jacket