This legislation looks to me like a classic case of Congressmen latching onto an issue that they think will make them look good ("what, you're against airline safety?"), but won't require them to actually directly spend any taxpayer money, since the costs are imposed on airlines (and hence, passengers). It's also a classic case of concentrated benefit (big upside for the companies that might be able to sell these barriers), dispersed downside (slightly higher costs for the traveling public).