Sandy Cheeks' treedome

I'm sure some people have noticed this, but there are times where SpongeBob and his friends have gone on land and haven't dried out or had trouble breathing. We see this pretty early on in the series where Sandy and SpongeBob and his friends are competing to see whether land or sea creatures are better, and we see it in the movies where SpongeBob and friends are walking around on land just fine, and in other episodes. But then we see SpongeBob and friends go to Sandy's house and need water helmets otherwise they'll dry out. So why is this?

It's actually very simple. It's the conditions. Whenever SpongeBob and friends leave the ocean, they always remain close by it. Now, in lots of books and shows and movies, sea creatures like mermaids and such that go on land are able to do so but can't go too far inland because they need to remain moist. This is the answer. The moisture in the air allows them to be on land without drying out. We even see this in the hibernation episode where SpongeBob and Patrick are able to take off their water helmets at Sandy's while it's snowing because the snow is water.

Now, jump back to Sandy's debut episode. She's showing SpongeBob around her treedome, and she specifically describes the air as being the, quote "driest, purest, most airiest" air. THIS is why SpongeBob and the others can't enter her treedome without a water helmet, because there is no moisture in the air to keep them moist like there is when they go ashore.

No literally

Okay, you know what? None of this would have happened if you didn't come back with your infestation!

All you've brought us is fleas and trouble and pain and itching and a rash! And pain and fleas and itching and... pain!

So... much... pain! So much pain...

And as for you!

If you hadn't thrown this party, we wouldn't be in this mess!

Wait a minute! You had as much to do with this party as I did!

You call this a party? I'm beginning to question our friendship!

I'm ready for the longest, coldest winter ever!

Bring it on!!!

Spring?

In "Tea at the Treedome", Sandy states that the dome is "made of the finest polyurethane, that's the fancy name for plastic." However, later on, the dome is seen breaking exactly as if it were glass?

Because of the right part of it, the amogus meme actually looks like it took place in SANDY'S TREEDOME, BIKINI BOTTOM