Shoulder bags have some advantages over other styles of bags. It is smaller and more convenient for shopping and weekend day trips. If your only needs are car keys, a wallet, and lipstick, there is no need to carry a large bag that appears flat and collapsed. It's more formal. On some occasions, such as a wedding or public speech, wearing a backpack or cross-body bag may not be dressy. A shoulder bag will add refinement and elegance to your overall outfit.