There are 2 major types of programs:
'post bacc' - for people who were not pre-meds who are looking to do pre-med work after an undergrad degree. Like an accountant who wants to be a doctor. I don't know of any of these that DO have a MCAT requirement. You don't have the classes, how can you take the tests?
'SMP', MAMS, etc - programs for people who were pre/meds, might have tried unsuccesfuly applied to med schools and are looking to prove themselves. I think most of these do have some sort of MCAT requirement, but I'm not sure.