I don't know what's common for others. For me, stopping for a sit-down breakfast is very enjoyable. My favorite breakfast café is about 6 miles from home. I ride over, get a nice breakfast, then go for a ride. For the record, I'm not much of a hurrier when I ride - more of a mosier. I take it easy when my stomach is freshly filled and my legs are cold. My legs warm up quickly; the feeling of having a full stomach goes away quicker, but I don't mind.

I'm a self-contained tourer. On a long tour I'm always hungry. I typically have oatmeal or a bagel for "first breakfast" while I'm breaking camp and packing up, then stop 5-10 miles down the road for "second breakfast" at a restaurant. It works for me.