One main stat of Rising Star is FANS. The more fans you have, the higher STARBITS(SB) you can get. Let's compare the Illegal Busking rewards of a player with 10 fans(L) and 11K fans(R):
As you can see, the "fans buff" made me able to get 238 more STARBITS than usual (1 - 8)!!! How about other missions?
As you can see, the "buff" is constant regardless which mission you play. So how does this change your game?
Well, let's take a look at Saturday Headline Mission: 
- Without the "buff"(10 fans), you're guaranteed to get 350 to 1404 SB.
- At 11k fans, you have a 85.5% chance get 350 - 1404 SB and a 14.5% chance to get 1405 - 1639 SB.
- 14.5% chance to get more than usual. not bad, eh?
Now let's take a look at Illegal Busking: 
- At 10 fans you can get 1 - 8 SB.
- At 11k fans, you can get 1 - 243 SB. You have 13.3% chance to get 1 - 8 SB or 96.7% chance to get 9 - 243 SB.
- At 95% you can safely say that you will always get 9 - 243 SB!
To test it, I spammed Illegal Busking 4 times. Here's what I got: 
That's 90 NRG, 20 minutes, 603 SB, AND 4 chances of getting PIZZAS!
So to sum this up, fans increases your max SB per mission, AND the more you should play the basic missions. Illegal Busking (and Radio Interview) FTW!!!
Follow me for more unnecessary analysis and giveaways in the future!
Till next time!