I know people who wear their toddlers in slings and other carriers. If you get a good one with 2 shoulders, or a wrap, it's great. But the snugli and bjorn are definitely not made for bigger babies. Our bjorn has been in the closet since the baby was about 15lbs.
We had a great experience in the mall this past weekend. My daugther was up on my back, having a great time looking around or sleeping, and we used the stroller to carry our bags. There were definitely several jealous fathers loaded down with bags while their wives pushed the strollers.
Personally, I really loved keeping my baby that close, as opposed to a stroller (which were awkward to maneuver). I've had idiots run into the thing on several occasions (and not simple accidents, either. One frat boy at a theme park INTENTIONALLY vaulted over her like a track runner, I nearly broke his skull, too.) When she was little, it was great for face-time and interaction, especially taking her through the city (Boston).