I eat very boring bagels, slice it, toast it, spread on the butter, spread on the jam, done!
The reason I'm a boring bagel eater is because I'm not big on the whole "mixing foods together" thing, thats why I can eat a ham sandwhich or a cheese sandwhich, but I can't eat a ham and cheese sandwhich. It applies to pretty much all foods, to me it's all to do with texture. So I would never eat anything else in a bagel because it doesn't seem right to me.