Did a search of "Grandstand" in this section and nothing of interest came up, looked at suggested improvements log and found it not mentioned there. Although i'm pretty sure this has been mentioned somewhere, i can't find it :S

Anyway, what i suggest is that the grandstands should be filled in all of the track enviroments. It just makes LFS a more polished sim and in addition, as a driver, enables you to be more immersed in the driving experience. Not sure how much effort it would take to fill these grandstands, but just take those men who surround the BL2 track behind the fence, and make them take on a sit position shouldn't be too hard should it?

So, to further elaborate on this idea, i've broken it down into how much the grandstands should be filled depending on what kind of race it is.
Practice - Empty, noone in the grandstands.
1-5 lap race - About 25% full?
6-10 lap race - About 50% full?
11-20 lap race - About 75% full?
21+ lap race - 100% full?

Of course, instead of having it as the number of laps, it could also be determined by how long the race is expected to last for.

Fill them in based on how many people are watching the server on LFS Remote.

Quote from UncleBenny :

Fill them in based on how many people are watching the server on LFS Remote.

What about servers that aren't on LFSR?

Quote from LFSn00b :

No, actually i'd make it so when you hotlap the grandstands are empty, and when you go in full server, grandstands are full and from 1-10 people in servers it is 50% full.

What about a practice session, or offline?

What about offline with AI? People do actually play this game in single player mode ...

^ People...I for one play offline to test skins and stuff.

What about having # of players/AI determine how full it is?