The Star Wars films are one of the fictional settings that thrives on the idea of presenting tiny snippets of characters who you're never going to see again. It is, in fact, one of the endearing things about Star Wars - it gives a real sense that the heroes of the story inhabit a larger universe in which there really are millions of other people going about their business and intersecting with the heroes only briefly. The background gains depth and realism through this device.
You can do a similar thing in a roleplaying game. However, the interaction level is different, and without the aid of visuals it can be difficult even getting across to the players that there are minor characters flitting around in the background. Also, too many "name" NPCs can get confusing. Especially if you're trying to make each one memorable as a character in his own right. Our GM is actually stretching himself perhaps a little too thinly here.
Transcript
Count Dookû: Ah shall show you all ze evidaunce we need to conveenze ze ozzer Separatists to act!
Nute Gunray: And what do you ask in leturn?
Count Dookû: When we 'ave oversrown ze Republic, we weel need ze strong leader...
Shu Mai: I theenk it should be mee, señor.
San Hill: Nu, I'd meke-a a better leeder. Hurty flurty schnipp schnipp!
Wat Tambor: You fools! It shall be I!
Nute Gunray: Sirence.
Count Dookû: Ah would be 'appy to, 'ow you say... contest mah mettle against zese worzy genteelmen.
Nute Gunray: A reader will be chosen flom amongst our arriance in due course. Those who wish to contend should demonstlate their abirity.
Obi-Wan: You know those improv classes Annie and I went to?
GM: Yes?
Obi-Wan: I just wish they could have seen this.