I have successfully published a comic book that was political satire. You don't really need anyone to be able to publish a book. Once you get an IBSN number you can register your book, and booksellers will put it up for you. You need to do some marketing and advertising, and you are good to go. To paraphrase a comic line " Publishing is easy, Marketing and Distribution is hard". Yes I know it is grammatically incorrect. Unless a vanity press can offer a valid marketing and distribution campaign, then it would be a waste of money.
Today there are a number of sites that will put your eBook online, or print a book for you at a fairly reasonable rate. CafePress, LuLu, and Amazon are only three of the options open to you. It really depends upon what you want to accomplish.
I just wanted to do it, so I did.
Google "The Shrub Chronicles"
And you will see it.