They're probably using condenser enlargers because they got them old and cheap! And I personally cannot think of any negative I couldn't
print using a diffused light source. Once in awhile someone will want to preserve some very distinct visible grain effect; but many people who
do own condenser heads alter them for diffusion them anyway. There are decades of arguments over this subject in print, but much of the logic
seems obsolete now that very high quality variable-contrast papers are commonplace, along with fancy developer tweaks with accomplish the
same kind of thing with less pain.