Share / view files betweek Mac OS X and Linux (Ubuntu) using sshfs and GUI
Looking at your command to mount your Linux drive on Mac,
sshfs user@192.168.0.2:/ localMountDir

it looks like you are specifying that you want to mount the root of the Linux filesystem (that’s the :/ part). In general, most operating systems assign ownership of root-level directories to a privileged user (i.e., not you). In the case of Linux, root is the name of the superuser and wheel is the name of the group to which root belongs. So what you are seeing is, in fact, 100% correct. And it’s also no surprise that permissions become more restrictive as you descend into certain directories (e.g., if you are trying to cd into your own home directory then it’s expected that it is not world-readable [750], whereas the root of the filesystem should be world-readable [755].)
What I suspect you’re wanting to do is to sshfs directly into your own home directory on the Linux box. So you’d want to specify that on your command line:
sshfs user@192.168.0.2:/home/YOURUSERNAME localMountDir