Ok so I have a theory of what happened to Spamton,
What we know is that he was a salesman that wasn't able to sell anything, one day he contacted someone or someone contacted him, from that point he became a great salesman to the point that he lived on Queen's mansión, that person stopped helping him and all his sells went down, the day he was going to be expulsed from Queen's mansion one of his old friend's came to see him, but he only found a phone in the middle of a phonecall with garbage noise.
I will go about explaining this from point to point.What did Spamton sell?:
The game give us different clues about what Spamton's big shelling item was
Firstly the poster on the alley on wich first meet Spamton, it's for "BIG SHOT AUTOS" and it features and image of Spamton implying he used to sell cars, this on top of the fact that his store is
sorrounded by broken cars confirms that this is basically what he primarily used to sell.Why did the sell's stoped and the two phone callets theory:
While is usually assumed that Gaster is behind Spamton's rise and fall due to the "Garbage noise" on the last phone call, but what if Gaster only did that last one, "Then who is the guy that helped Spamton on becoming a Big Shot?" you may ask.
Well I think the answer is Mike, but who is Mike?
Acording to Spamton, "he is a criminal despite what you might see on TV"
My theory is that mike was an scammer, let me explain, firstly the cars that Spamton used to sell are identical to Queen's car:
Mike's real identity and the cars model are important to understand this next piece of information:
According to Queen "she is concerned about the fact that her car hadn't exploded yet" meaning that this tipe of car has the habit of randomly exploding.
With all of this in mind let's check how Spamton's story is going:
Spamton used to be a salesman who couldn't sell anything, one day is contacted by a man named Mike that tells Spamton how he can help him become a Big Shot, Mike give's Spamton car's that he sells, they work as partners splitting the money, this car become's really popular to the point that Queen herself hires Spamton for her mansion so she can have as many cars as she wants, the cars start to malfunction and explode resulting on numerous Lawsuit's, Spamton loses all of his money to this while Mike just scape's with his part of the money.
This is all speculation so I could be wrong but it will help explain a lot of things about Spamton, with all of this out the only thing left is:Gaster:
The second caller is obviously Gaster, the "garbage noise" is the sound of the "17 entry" with confirm's that Gaster talked to Spamton the day he was gonna leave Queen's Mansion, we can assume that Gaster told Spamton something similar to what he told Jevil, that none of this is real and is all just a game.
unfortunately there's not enough information to pice together the rest, or at least I don't.
This is all speculation and could be wrong but it's been on my head for some time, feel free to tell me your own theories or why mine is wrong