Are you saying WI and VT have reciprocity will all states? I was not aware that WI didn't have a bar exam, that's surprising. I know of at least two states that have reciprocity with no one (DE and RI). I was under the impression that reciprocity is a two way street. Can reciprocity be one way? Are you guys sure about this?
Wisconsin does not have reciprocity with all states. Wisconsin does not, for instance, have full reciprocity with California (or more specifically, California does not have general reciprocity like most other states do). People moving to or from California almost always have to take the local bar exam in some form.
Further, as far as I know, in each instance where there is full or partial reciprocity, one still has to satisfy the admission requirements of that state. So, for instance, when I (a member of the Wisconsin bar) joined the California bar, I not only had to take the "lawyer's bar exam" (same as the regular bar exam, minus the multistate), but I also had to take the MPRE - because it is not required in Wisconsin. Lawyers moving from Minnesota to California take the lawyer's bar exam, but not the MPRE - but it is already required in Minnesota. Transferring lawyers in any state also have to pass local background/ethics check, and the standards for those vary from state to state as well.
Similarly, as noted, graduates from a Wisconsin law school (i.e. Marquette and UW-Madison) do not have to take the Wisconsin bar exam for admittance to the Wisconsin bar. If and when they wish to practice in another state, however (not usual, with Chicago down the street), they have to take the bar exam in that other state, regardless of reciprocity.
As a general rule, "reciprocity" is not a waiver of general bar admission requirements, but simply a waiver of some or all of the written examination - if that examination has successfully completed previously.
So while I don't recall a specific instance of someone moving from California to Wisconsin, I would be more than surprised if Wisconsin did not require an ABA JD - because that is a requirement for admission to the bar in Wisconsin.