I did that with the Moby a few times. Mostly in church because I couldn't move around a whole lot (my child is a motion junkie), so facing out kept him quiet for an extra 10-15 minutes. And definitely not as comfortable!! You do what you have to do as a parent. Next kid I'll probably do a high back carry in a mei tai when they want to face force. Just won't work when sitting down.
I think the big reason behind current baby wearing thought of parent face only is how many parents have one of those carriers that Anna posted pictures of and only ever face their baby out. I know I've seen a kid hanging by their crotch REALLY low (no where near the "close enough to kiss") and kid was facing forward. This was at the Riverwalk Mall in San Antonio. Ran across them 2 hours later and the baby was still there in the same position crying her head off. How the heck the mom found that comfortable I have no idea!
I found this interesting post over at PAXbaby: http://paxbaby.com/tag/front-facing-out/
I never thought about doing craft with DS like this! Though I did face DS out in a ring sling (like I did in the bowling picture) when we were out to eat and he wasn't interested in food yet.
Here's a link that has 14 different celebs using Ergos! When I first saw the title of this thread, I thought for sure it was going to be about Ergos, because I feel like most of the pics I've seen of celebrity baby-wearing is done in Ergos!