This website supports that.
According to it, when existential sentences start with 'there', many people, particularly Americans, have the verb agree with the first noun. So "There is a dog, a cat, and a squirrel in the park."
However, other people use a plural verb if there are multiple singular nouns. So "There are a dog, a cat, and a squirrel in the park."
This site also talks about inseparable pairs, like 'salt and pepper'. It says in informal common usage, the singular verb is used. So "There is salt and pepper on the table."
But in more formal usage, the plural verb is used. So "There are salt and pepper on the table". Though doing a Google search, that produces very, very few results.
How is "sushi" supposed to be pronounced in Finnish? Should it be the same as in english, with the "sh" making the same sound as it does in english? In the audio for this sentence, it sound to me like it says "susissa" and I don't here the "sh" sound if it is supposed to be there.
What I've heard is a sound about halfway between an English 's' and an English 'sh' (heard also in "shamaani"). I gather that they're trying to pronounce the 'sh' correctly, but I'd guess the phoneme is only now entering the language in these foreign words, and so it doesn't come naturally to them. It's not as distinct as when a native English speaker says it.
I am also not aware of any other digraphs (two letters being used to represent a single sound) in Finnish, though they're very common in English. So it might be confusing to some speakers.