In most cases, no. American fiction is focused on the main narrative and doesn't commonly incorporate post-credit scenes. However, there might be some rare exceptions in experimental or unconventional works.
I Am the King of Monsters, Godzilla, was a novel about a man who was reborn as the king of monsters, Godzilla. This person was reborn as Godzilla in the parallel universe and successfully bound to a system, becoming stronger through devouring and upgrading. He had subdued all kinds of giant beasts and fought against the sleeping Titans from the immemorial era. In the end, he came to China and trained with another system bound person. The novel also contained some descriptions of the chapters, but the specific plot and story development needed to be read in full.
A post - credit scene scary story might involve a cursed object. In the main movie, the object seems harmless, but in the post - credit, it starts to glow and strange noises come from it. It then causes chaos in the empty theater where it was left. Also, there could be a post - credit scene where a character finds a diary that tells of a horrible past. As they read it, shadowy figures start to appear around them, and the words in the diary start to bleed, creating a truly terrifying moment.
Well, it depends on your interests. If you're a huge Godzilla fan, then it's a great read. It expands on the lore, shows different perspectives of the monster battles and the world around Godzilla. However, if you're not into monster - themed stories, you might not find it as appealing.
It can be quite important. It might set up future plotlines or introduce new characters. For instance, it could be the start of a new arc for a character like Qi'ra.
Well, it can be considered great. The movie creates a whole new world where these huge monsters exist. It has a lot of action scenes that are typical of science fiction movies. The concept of Godzilla as the king of the monsters is also very appealing. The movie also explores some themes like the relationship between humans and these powerful creatures, which adds depth to it.