Back in the days of season one, they barely had enough ponies to fill a background without resorting to duplicates and recolours.
 
Now look at this shot and just how many unique ponies there are against the number of duplicates and recolours.

Also there’s Silver Shill over at the left. Guess he’s gone legitimate business!
 
And it looks like Rarity (or a bald clone of her) is also an Incan princess/empress.

Nobody noticed what appears to be Bulk Biceps’s mother/wife (next to the glorious stache’ pony)?

@MidS  
Whaaaaaa…headcanon accepted. It’s pretty likely this was the work of an animator having fun

Seeing Prince Blueblood sitting there among the foreign dignitaries makes me wonder just what the hell his job is. Prince Regent? Secretary of State?

@JP  
“What did Cherry Jubilee do to get a place in the VIP section?”
 
She’s the Littlefinger of Equestria…

Wait, that large pony near the bottom left corner of the VIP box. Is that….Bulk Bicep’s grandmother?

What did Cherry Jubilee do to get a place in the VIP section? And why isn’t Coco sitting next to Rarity (perhaps they haven’t noticed each other?)?

Wow, Mayor Mare actually got a spot in the VIP section? Finally, some respect.

Amira is HUGE compared to Fleur de Lis. I like it.

@RIG  
People just like Drawing her that way man, cant stop people from drawing what they want.
 
Also Hey look! It’s the pony that Quite hanging with Flim and Flam!

I spy with my little eye, something that starts with “what the f*&k.”
 
Two Cheerilees

i see the pony which everyone draw as an amputee, and she looks 100% ok.

Third screencap of this part I have to tag, yay! XD
 
Still some ponies that have names, but not ones I remember, and ponies that are recolors of names ponies, but don’t have names on their own, thus that are untagged. Have fun!

@Background Pony #EC20  
Man, sweet desserts really are the way to a princess’ heart! Sux2bu Applejack.  
 
Totally AJ looking down the VIP box.

Let me take a stab at this; I see Braeburn, I see Silver Shill, I see Sheriff Silverstar, I see Coco Pommel, Oh, there’s a lot of ponies I recognize here.

Have fun tagging this one!

… Wait, I just found Cheerilee at the bottom left corner, and then towards the bottom center, I found Cheerilee… Her twin sister?

I also see Hoity Toity and Sapphire Shores a little below Shill, And Coco Pommel right below them.

@Inkan1969  
Nope. Different guy.

@Cerebrate19
 
I see Rumble next to Cheerilee. But I think that’s Maud immediately below and to the left of Pinkie Pie.

@Inkan1969  
i think that´s rumble

I also totally see Silver Shill in the center left edge selling something…
 
Also, Napoleon Pony is best pony…

Maud Pie and Cheerilee on the bottom left?

Braeburn and Mr. Waddle on the bottom right.