FLOTSAM

A lot of things wash up on the beaches of Golden Island.

Sure, you'll get the usual plastic waste and all...

'I went over to investigate. The bundle was black and covered in gunk. For a second, I was afraid it might be alive, but when it didn't move, I decided to be brave and bent down for a closer look.
I poked the bundle and then backed off, ready to flee, but when it still didn't move, I went over to check it out.
Trash. It was nothing but garbage.'

...but more often than not, you'll also get lots of useful, and even valuable stuff from the ocean!

'(...)very own band, The Friends. Out stage is kind of---how can I put this?---shaky and rickety. Dahlia built it out of random pieces of wood she found down by the stream, and it's pretty wobbly because there aren't any nails in it. While Dahlia(...)'
Highlighted is the line 'Dahlia built it out of random pieces of wood she found down by the stream'

'I set up an old record player in the ballroom. It had washed ashore along with a box of records, and Dahlia had gotten it working for me---back when we were friends. It was a little warped and(...)'
Highlighted is the line 'It had washed ashore along with a box of records'

And it's not like they just accidentally stumble across these while going on a picnic or something and go 'huh, neat!' before putting it in their pocket.

No, they actively scour the beaches whenever they need something, and get upset when the ocean doesn't magically give them what they want, because it's genuinely a steady and reliable source of resources for them!

'Of course, I knew that the other birds would find my mystery pretty quickly. That was all part of the plan. I'd had the pigs build it on the beach where I knew Poppy came every morning in search of junk that had washed up. Seriously, every morning(that bird is sooooo predictable).'
Highlighted is the line 'Poppy came every morning in search of junk that had washed up.'

''Yeah, I hope it doesn't collapse. I did my best, but I couldn't find a single nail on the whole island,' Dahlia said in a sorry voice.'
Highlighted is the line 'but I couldn't find a single nail on the whole island,'

THAT's the rate at which flotsam flows in!

This isn't exclusive to Angry Birds Stella either, it applies to the Angry Birds world in general.

Foreman Pig holding a bag of golf clubs, telling Matilda 'Five weeks of doing your chores! And I'll throw in these peculiar sticks I found on South Beach!'

Corporal Pig knocking Foreman Pig aside, holding an ATM machine, telling Matilda 'SIX weeks! And this thing *Huff Huff* that I found on South Beach.'

Red, Bomb, Chuck, and Jay Jake or Jim, looking at a crate full of Tyrkisk Peber Volcano that had just washed ashore.

Notably, in Angry Birds Epic, flotsam is the MOST COMMON of resources, and is required to craft every piece of equipment in the game.

A screenshot of Angry Birds Epic, showing various crafting materials in an inventory. The focus is on 'Flotsam', of which I own 230 of.

Look, I know all of this means absolutely nothing, and is simply a handwave to explain why these wild birds and relatively less wild pigs have all sorts of cool shit that they don't have the tools and knowledge to make yet, but you have to admit...

Corporal Pig on a ship, looking at massive pile of items, including a bicycle, a beaten-up washing machine, a TV, a beaten-up car, several giant tires, a drawer, and other things I'm too lazy to describe here.

This IS a lot of flotsam!

It all has to come from somewhere!

Did an ungodly massive cargo ship crash somewhere nearby?
Did the exact same thing happen again near Golden Island?

Why do shipwrecks happen wherever the Angry Birds are?
Are THEY behind it?

A yellow bird named Poppy, sporting a devious, creepy smile.