The B-ranks (named mobs with a "passive" blue icon) don't give rewards for killing them, unless you have them as your weekly hunt mark. Calling them out is always good practice, because even if you don't personally need it, someone else might. Do everyone a favor though, and include the rank of what you're calling so people know it is or isn't a mark they get seals for--A-ranks are worth more than the 1/2 star bills combined, so calling an A-rank is going to draw a crowd quick.


Also, yes, in a quick breakdown, there are three tiers of hunts:
1, 2, 3 star bills (daily). These give overworld mobs you need to kill, and you can start doing these at 53, 56, and 59 (respectively). 1 star is worth 15 seals, 2 star is 20 seals, and 3 star is 75 seals.
Elite bill (weekly). This assigns you one of the B-ranks that can spawn in Heavensward areas, and these are worth 100 Centurio seals. B ranked mobs have unique names, and a blue icon next to their name--these are the easiest to find because they're always non-aggressive (which is less common in Heavenward areas).
Open world kills (A/S ranks). These mobs spawn randomly in the Heavenward areas (as in they don't have a specific area they appear in), and S-ranks usually have special conditions that need to be met before they can appear. These give the most reward for the least effort if you have a hunting LS or know when to look for them. A and S ranks have unique names and a red icon next to their name, because they're aggressive and will attack anyone who comes near them. People who don't know this (or are trolling) can pull a hunt mob this way, and the phenomenon is called a "facepull" because someone walked right into the mark, triggering an avalanche of waiters to unload on the mark instead of waiting for anybody else who was on the way.