I would never recommend that one use these under already padded shorts as that tends to make me hugely LESS comfortable, not more. So don't wear these under already padded shorts or tights. If you've got shorts that are not comfy try different shorts, or different saddle, or go get your bike properly fit or all 3.
I keep a pair for travel like if I'm going somewhere I might ride a rental and don't want to pack a lot of gear. Shorts, gloves that's about it.
Also commuters, wear the clothes you wear to work just with these under. Nobody can tell you rode to work.