Yes, not every pet capable caster NPC should cast a pet by default.
The info at Allakhazam can help you to find out what NPC in what zone has a pet.
http://eqbeastiary.allakhazam.com/zonelist.html
Look for "<NPC> pet"
Eg. in Old Sebilis:
...
froglok krup mage
froglok krup mage pet
...
Tolapumj
Tolapumj pet
Anyone knows how EQEmu determines if and how a NPC gets a pet?
I did have a look into the table npc_types but didnt see anything resembling an 'has_pet = 0/1' entry.
Btw.: According to Allakhazam there are no pets in droga.