Orcs and hobgoblins: what’s the diff?

As 1d4chan points out, there isn’t really that much of a difference between hobgoblins and orcs. There’s any number of ways you could world build a more convincing explanation in my opinion.

Here are some ideas I've seen elsewhere:

• Maybe there isn’t a difference, with the two being ethnic groups within the same species. After all, in earlier editions of D&D both kobolds and orcs were considered goblinoids.
• Wayfarers posits that hobgoblins are actually half-goblin and half-orc. 
• Some settings depict orcs as pig-faced, such as early editions of D&D, many Japanese anime, and the 3pp supplement Animal Races: Clan of the Pig.

I really like the pig-faced orcs option, so I think I’ll lay out some ideas I had regarding that.

• My setting uses Moorcock’s beast lords, who were adopted into some editions of D&D. They act as the patrons of beasts, druids, etc.
• Orcs are the porcine beastfolk. Their patron is the lord of pigs. I identify him with the Celtic god Moccus for simplicity.
• Borrowing a page from Tolkien’s old notes, Moccus’ creations are not a self-sustaining race. They are born from spawning pits and farmed like vegetables.
• The many varieties of orcs—like ghost-faced, orog, ogrillon, high orc, etc.—are bred by throwing creatures or body parts thereof with the desired qualities into the pit’s digestive juices. For example: humans, goblins, ogres, elves, other orcs, etc.

That’s all I have for right now. I hope to expand upon my ideas concerning orcs in the future.