Why not papoose bags?

NTSB wants child safety seats on airlines

The NTSB is recommending that parents strap young children into safety seats when traveling by air -- a recommendation that could make travel significantly more expensive if it becomes mandatory. The safety board says lap infants can be severely injured in severe turbulence or survivable crashes when parents are unable to maintain a hold on them. Child seats are a better option, the board says, but that would require the purchase of an additional ticket. KSTP-TV (Minneapolis) (5/27)

Here's an idea. Why not a papoose bag? Or an infant carrier that a mother wears over her chest? Do we really need infant seats on planes?