The text cited in the OP's query is taken from a 2012 book by the economist and philosopher Michael J Sandel titled What Money Can't Buy: The Moral Limits of Markets.
Drawing most of its examples from the USA, its core theme is the question of how to strike an appropriate balance between those arrangements and institutions in society where it is reasonable to allow the free market to operate, and those where it is inappropriate.
The full context for the question posed by the OP is a comparison of the appropriateness of allowing people to pay for expedited processing through airport security versus the paid-for opportunity to jump the queues for theme park amusements:
Critics complain that a fast track through airport security should not be for sale. Security checks, they argue, are a matter of national defense, not an amenity like extra legroom or early boarding privileges; the burden of keeping terrorists off airplanes should be shared equally by all passengers. The airlines reply that everyone is subjected to the same level of screening; only the wait varies by price. As long as everyone receives the same body scan, they maintain, a shorter wait in the security line is a convenience they should be free to sell.
Amusement parks have also started selling the right to jump the queue. Traditionally, visitors may spend hours waiting in line for the most popular rides and attractions. Now, Universal Studios Hollywood and other theme parks offer a way to avoid the wait: for about twice the price of standard admission, they’ll sell you a pass that lets you go to the head of the line. Expedited access to the Revenge of the Mummy thrill ride may be morally less freighted than privileged access to an airport security check. Still, some observers lament the practice, seeing it as corrosive of a wholesome civic habit: “Gone are the days when the theme-park queue was the great equalizer,” one commentator wrote, “where every vacationing family waited its turn in democratic fashion.”
It is apparent from this more complete context that here, morally less freighted must mean morally less fraught, i.e. 'less heavily beset with moral complications'.
(Note that the questioner incorrectly quoted morally less freighted as spiritually less freighted, which is not at all the same thing.)