That is the case, and a bit of quick googling suggests to a greater degree than I expected (depending on film and optics I saw estimated ranges of MF being able to resolve the equivalent of 80 to as much as 150 megapixels! I guess it makes sense that modern medium-format digital backs are often in that kind of range).

If a digital SLR and a light table can get you enough resolution for what you want to use the images for though, that's fine. You could use that for most of your images and then get the ones you want to print really large professionally scanned later.