This is a common reaction, especially from people who aren't British. It's a World War II thing; privation in England during the war was so bad that children would betray their families for a confection that basically tastes like snot dusted with powdered sugar. (The fact that Tolkien and Lewis were both writing in the wake of WWII food rationing is why modern high fantasy has such a rich tradition of Food Porn scenes)
A lot of it is that later writers who hadn't lived through rationing grew up reading Tolkien and Lewis and so saw opulent feast scenes as "Just a thing you do in fantasy novels". JK Rowling included scenes like that in Harry Potter too, even though she's too young to have experienced it for herself.