EVERYTHING's illegal in Maryland, even sparklers. I do remember, when I lived in Accomac, that many of the smaller country stores there sold things openly I could only buy under the counter in Fairfax.
One year in Fairfax my brother came up to me at the fireworks stand JUST as I was convincing the dealer to sell me the (illegal) fireworks that I wanted. I could see in his eyes that he actually had some, but was scoping me out to make sure I wasn't a cop. Bro came up at the tail end of the conversation & said "...Aren't Jumping Jacks illegal in this state?" Dealer's eyes slammed shut. "Nothing like that here, sorry."
It must be by county in Maryland, because I can't imagine WalMart selling fireworks if they were illegal, especially in huge displays right as you come in the door. I was in the Pocomoke WalMart last week and nearly bought a big set of them.
I bet you were ready to kill your brother over that.
Not true, Maryland legalized ground based class c fireworks the last year Glendening was Governor. As I've always said thats his greatest accomplishment.