There are two arcane characters mentioned in the adventure, and neither of them advertises their skills. If confronted in battle, they aren't going to hide the fact, and they don't go around suppressing rumors about them.
In general, the treatment of magic and magic-users varies from fear and fearful respect to outright hostility. Arcanists are likely to be known for other matters than their spellcasting, such as being a sage or alchemist, or other such things.
Oh, and everybody can feel free to look up the information for their character's home area without a roll. There are no absolute secrets in the sblocks, merely information that not all characters are expected to know off the cuff.