It's not a Tuna Melt with out the cheese! The cheese is what makes a Tuna Melt a Tuna *Melt* because you melt the cheese on the tuna... A Tuna Melt without the cheese is just a warmed tuna fish sandwich! lol.
I live in the Pacific Northwest, USA and I *love* cheese with my seafood... granted you have to be mindful of the flavors of the seafood and the flavors of the cheese... if it's a strong seafood (like crab/lobster) or a more mellow seafood (like tuna fish/shrimp/scallops) and knowing how to pair it with a cheese that *doesn't* overpower it... one of my favorite dishes at The Olive Garden is their Seafood Fettuccine Alfredo, and when they pull out their little cheese grater thingy (I think it's parmesan) I let them pile it on...
does anybody remember that commercial for the Olive Garden where the waiter is spinning the handle, grating the cheese, waiting for the person to say 'when' but they pass out, and then the next waiter takes over, and they pass out, and then the camera pans back and there's a *huge* exaggerated pile of cheese on the soup bowl and there's about 10 waiters passed out around the table? I'm like that... only much less exaggerated... lol
To the OP's curiosity of people's traditions... growing up, my mom was very much a 'meat and potatoes' sort of American style cooking (she grew up in Idaho) and my dad cooked with a more Italian-American style cooking (he was born in Chicago and grew up in California, but his father grew up in Chicago in an Italian neighborhood)...
Personally, I'm certainly not a 'traditionalist' or a 'foodie'... I'm more of a 'comfort food' eater... I like things that taste like 'home'... things like raw, undercooked beef/steak makes me queasy... I like my meat to be *well done* without *any* hint of pink, let alone red... to me that just means you didn't cook it long enough and it's still bloody and raw and nasty. As for Sushi? Forget About It! I won't touch it... any kind of raw meat is just asking for food poisoning, IMHO. My parents style of cooking has certainly shaped the flavors I like or don't like... my mom cooks with simple, mild flavors so I hate spicy foods, but with my dad's Italian-American style cooking, I love garlic and onion powder (not so much actual onions) and marinara and alfredo sauces, and all those great italian flavors... just as long as it's not *spicy* lol.