In contrast, the Port Authority and M.T.A. charge tolls on their bridges, but independently set the amounts based on their financial needs. “You’re buying more than the bridge when you pay that toll,” said Robert E. Paaswell, a civil engineering professor at the City College of New York. “In theory, tolls are supposed to go away when a bridge is paid for, but that rarely happens. The costs are skewed because in addition to maintenance, they are used by different agencies for different purposes.”

Tolls from the four Port Authority-run bridges — the Bayonne, Goethals, Outerbridge Crossing and George Washington — and the Lincoln and Holland tunnels are used not only to support those crossings but also public transit services, including the Port Authority bus terminal and the PATH train system. Ron Marsico, a spokesman for the authority, said that it “consolidates the revenues from all its operations to meet the capital investment and operating needs of its facilities.” The last toll increase was in 2011, and less than 15 percent of drivers — those without E-ZPass — currently pay the full $15 cash toll, he said.

The M.T.A. operates seven bridges, including the Verrazano, which was the longest suspension bridge in the world when it opened in 1964 with a toll of just 50 cents. Today, it is one of the city’s busiest links with, on average, 196,000 vehicle crossings per day on weekdays, of which Staten Island residents account for about 75,000 crossings per day, according to M.T.A. data.

M.T.A. officials said that the $17 toll is higher than its other bridges because it is priced to cover the return trip. A federal law pushed through by then U.S. Representative Guy V. Molinari, a Republican from Staten Island, converted two-way toll collections to one-way in 1986 to reduce commuting times and air pollution on the Staten Island end of the bridge. Similarly, in 1970, the Port Authority decided on one-way tolls on traffic going into New York City to reduce congestion and emissions.

The M.T.A.’s other major bridge crossings — including the Bronx-Whitestone, Throgs Neck and Robert F. Kennedy (formerly the Triborough) — all charge a top toll of $8.50 each way, for a total of $17 round-trip.

The Verrazano toll has long riled local residents on both sides of the bridge, many of whom subscribe to an enduring urban myth — repeatedly debunked — that the bridge was supposed to be free once it was all paid for. Instead, the toll has steadily crept upward, most recently by $1 last year.

“It’s not because the bridge is getting more expensive,” said Samuel I. Schwartz, a transportation consultant who has proposed reducing such tolls as part of a congestion pricing plan. “It’s because we need more and more money to pay for the subways and trains coming into Manhattan.”