This is true, and I bet that it will be fixed in Project Jumpgate (the next tech coming to Roll20 that has been Announced). For a workaround, in the meantime, the best you can do is Expand the Page Size to something larger like 50x50 or 80x80, and shift your Map contents into the center. This will give you the power of panning without necessarily zooming. The workaround is really a pain if you're playing Pre-existing Module Pages that are already set up. The workaround is excellent and easy if you are just-now starting to build new Pages with Maps, since you can set the Page Size in the first place and center your map contents in the first place.
