(ABC 6 News) — Members of the U.S. Senate are taking aim at airline executives during a hearing about so-called “junk fees.”

A subcommittee is calling out the charges customers pay for early boarding, better seats, and other conveniences.

Senators claim there is a lack of transparency, and the vague pricing makes it hard for customers to budget.

Some believe the federal government should review and perhaps fine the airlines that use these fees.

Airline executives reject the claims and say the services are optional.

Government data also shows airfare has fallen about 30% in recent decades, but that does not include any additional fees.