Overpriced? That is up to you.
Do you really want to shoot an LC-A or a Diana, or Holga? Is that the look you are going for or really need for your project? If that is the case, and you can afford it then the market value is there to justify the price.
Are you looking for a camera that shoots film and you can put in your pocket but don't care if your photos have the LOMO look? You can lay your hands on a nice point and shoot pocket camera made by a major name camera company for about $10, you want brand new, you can get a whole lot of Kodak or Fuji single use cameras for the same money. These cameras will all take photos on film, and you could even create art with them, but the camera and photos will not have that LOMO look. So for someone that wants that look, these are overpriced.
I have a Nikon N90s with a Tamron 28-200mm lens, the entire setup cost me around $150, that is my go to setup for most of my shooting. Some people would say that was too much. For me, this is the setup that produces photos that I like so it was worth it, I might have been willing to pay more than I did for it even.
When something is a tool the price on it is a reflection of the work that went into it to make it function the way it does, when something is a fashion item the price is a reflection of what people are willing to pay to be hip and cool. Like designer clothing that ends up in piles to be made into rags, all fashion soon goes out of favor and something new takes it's place.
Remember you can't equate your joy to the number of dollars you are willing to pay for it, but someone out there is going to try and figure out how many dollars they can get from you so that you can have something that makes you happy.