To point it out, naval vessels are away from dock for extended periods of time and are often in places that don't have docks themselves - they need people always on hand in case something important breaks. Combat vehicles, on the other hand, require relatively little in the way of maintenance bays, and could probably receive most lower-mid level repairs in what amounts to a typical barn. They don't need actual tech crew with them - they can always be called up from the rear if need be and be there in an hour or two.
The clans apply the "warrior" term relatively loosely but also very definitely, basically coming down to whoever is allowed to hold a weapon is a warrior - the term applies to even paramilitary forces, such as the police, why would police deserve "warrior" status when those actually taking to the field of battle don't?
Now given the reminder that a big point getting the Wolverine's annihilated was based on their relative mobility between castes and the speed they were building up, it wouldn't surprise me if the crew were ex-technician caste. Or that most of the infantry were ex-laborer caste, with only "true" warriors taking up the sergeant and higher slots. But, in my eyes, all of these would be considered warriors.