I'll tell you how I picked up this habit. You know how in some French restaurants they give you butter and dijon mustard with your bread? They do. They sweet butter complements the spicy mustard really well. So it's not some weird combination I just made up. I thought since they tasted good together on bread, they'd probably taste good on toast, too. Since that's bread. Just toasted.
Totally unrelated, but I'm so exhausted right now. After riding my bike all over creation today, I just carried it up three flights of stairs. Ugh. (47 steps in all; my mom counted when she was visiting.)