Lol. Got me there - I have, I just blocked it out as I don't think I've ever "toasted" it (warmed in a microwave or pan, or on the grill) and I always referred to it as "iced"rather than "frosted" (frosting generally considered thicker). So hearing "frosted" and "toast" had my brain conjure the image of a slice of white/wheat/rye dolloped with vanilla frosting.
Sidebar: this reminds me of when I relocated to State College in 2010. I was told that natives of central PA are known for their love of peanut butter. I didn't pay it much mind; lots of people like peanut butter. One day I was in a bakery and a pan of cinnamon rolls with caramel icing caught my eye, as caramel icing (and frosting!) was always a favorite of my mom and grandmother. Only it wasn't caramel... but peanut butter. A combo I'd never seen before.
Seeing it seemed to open my eyes to the peanut butter passion, as I suddenly noticed that every cake, gob, cupcake, donut, brownie, etc. that was offered with any kind of frosting had to have a peanut butter variety available. I also started noticing the large sets of Tastykake with peanut butter varieties front and center, Reese's cups dominated Halloween candy displays, and ice creams had numerous flavors incorporating it (fine by me - PB in ice cream was always one of my favorites).
Another central PA favorite: scrapple.