Good Afternoon Jesse,
If I hear what you're saying, it sounds like you are referring to the sections of Collingswood (and other towns) that literally connect to South Camden. It sounds like your research has showed you reasonable home prices in the areas right next to Camden, and you're wondering if there is a reason for this. Please correct me if I am wrong.
If that is your question - yes, there is a reason for this, and it is very simple. Location, location, location. While Collingswood is a wonderful town, the neighborhoods and other towns that directly connect in and around the Fairview section of Camden do have lower resale prices. You can probably see why this would be the case. There are many beautiful homes in West Collingswood/Oaklyn, however, the area is often viewed as "less desireable" by many people because of it's proximity to Camden, Route 130, white horse pike, The Heights Apartments, and the commercial corridor that exists in that area.
If you find a wonderful home for the right price, go for it! Hope that helped to answer your question.