Fishing - Dumb question abouyt sharks

I feel like I should know the answer to this question, but I don't. Last
year, I caught a small shark...20 lbs or so, near Little River, SC. I'd
done this many times before. As I have always done, I held the shark behind
the head, just forward of the dorsal fin. I was able to remove the hook
(with pliers of course) and release him unharmed. While talking to someone
back at the marina, he said something about being careful about the barbs on
the sharks and that they would stick you. Several other people there agreed
with him and said that they had venemous spines. I have caught and handled
lots of sharks and never once remember seeing any types of spines on them.

I am familiar with Horned Sharks and Spiny Dogfish, but don't know of other
species of sharks that have spines. They said that all sharks had them and
I just don't believe that. I've never seen any spines nor have I ever been
poked / stung or whatever else they allege that these sharks can do.

What's the truth?