The notion of existence is doing a lot of the leg work. A epistemological solipsist can say things "exist" when they have a model of their subjective experience in which things can exist. It gets real funky because your interpretation of qualia results in a model that includes the brain and thus a model of how you are interpreting things as a model in your model.
Perhaps it's acceptable in moderation, like "ain't". It's needed for a rhyme in a well-known song by Billy Joel, for what it's worth. On the other hand, there is a different song by Billy Joel in which "anyway" is used for a rhyme.
No, I'm not a Billy Joel expert or fanatic. I just happened to notice, all right?