With its weekend ridership plummeting, BART has dispatched marketing representatives to stations throughout the cash-strapped system to hand out 25,000 free round-trip tickets in the hope of luring back customers.

The number of weekend riders on BART slipped more than 10 percent in the past two years, while weekday ridership remained relatively unchanged during the same period, according to BART records. The weekend decline cost the system an estimated $15 million.

The free round-trip tickets to any of the 46 stations on the 112-mile line are only good on weekends until Dec. 18.

“Discover exciting new BARTable destinations,” read the backside of the orange and yellow tickets.

Officials suspect the weekend ridership drop is the by-product of track renovation, which requires the temporary closure of some East Bay stretches. And the growing popularity of ride services such as Uber and Lyft, which offer door-to-door service at a competitive price, is also blamed.

A’s fans at Coliseum Station were given 1,500 weekend passes during three separate weekday games over the past five weeks.

An additional 10,000 freebies were given out on Aug. 17 at San Francisco’s Embarcadero Station, and the same number at Montgomery Street Station a week later. And on Thursday, 2,100 free tickets were handed out at Downtown Berkeley Station.

At an average cost of about $7.60 per round trip, the free BART tickets are worth about $194,560.

More ticket giveaways are planned in the coming weeks, though officials aren’t disclosing where and when.

“We prefer to give people a nice surprise,” BART spokesman Jim Allison said.

He added the promotion is meant to encourage regular BART commuters to try out the system on their days off — and maybe to bring along paying friends or family members.

Allison said BART will be tracking the use of the special tickets to see if they actually work.

“We are not just giving them out willy-nilly,” he said.

The BART promotion also gives riders a chance to win a $300 Clipper card if they take part in a brief survey about, among other things, where they went using their free ticket and if they brought a paying rider along with them.

BART has been running at near capacity during commute hours, clocking in more than 200,000 round-trip riders on an average weekday.

Weekend and night ridership, however, is another story.

The first big downturn was last year, when weekend ridership dropped more than 4 percent — or an average of nearly 14,000 passenger trips. It probably would have been worse had it not been for the 2016 Super Bowl played at Levi’s Stadium in Santa Clara, which brought near-record weekend ridership to the region in early February.

But the weekend decline accelerated in the past year — with the loss of an additional 7 percent of riders, or an average of 23,562 combined every Saturday and Sunday.

BART has had its share of bad press in the past year. In addition to elevators and escalators constantly out of service, there has been growing concern in recent months that the commuter railroad has become a rolling homeless shelter, raising concerns about safety.

Last week, six passengers — including a Pleasanton man and his family who were attacked and robbed last spring when teens swarmed a BART train after it pulled into Coliseum Station — filed suit against the agency for gross negligence.

No so free speech: The cost of San Francisco police playing cat-and-mouse with the Patriot Prayer demonstrators last month is in — and it was not cheap.

According to the San Francisco Police Department, the direct cost to the force for the “First Amendment-related events” on Aug. 26 is estimated at $775,000.

“This includes planning during the week leading up to the event,” spokesman Sgt. Michael Andraychak said.

Andraychak said 98 percent of the tab was for overtime pay, with the remainder being incidentals such as van rentals, and food and water for officers in the field.

The tally doesn’t include the $10,000 that the Recreation and Park Department spent fencing off Alamo Park.

Tower talk: As the Millennium Tower continues to sink, the legal costs continue to rise.

On Thursday, the Transbay Joint Powers Authority approved an additional $1.5 million in attorney fees to the firm of Jones Day to help fend off developer and homeowner claims that construction of the Transbay Transit Center next door contributed to the sinking and growing tilt of the 58-story residential downtown high-rise.

The added money brings Jones Day’s bill to $3.5 million since it was hired in December.

“It is anticipated that the maximum compensation may be increased in the future as the need arises,” according to a staff memo prepared for the Transbay authority’s Sept. 14 meeting.

The good news, Transbay officials tell us, is that they anticipate a large portion of the litigation costs involving the Millennium Tower will ultimately be paid or reimbursed by either the contractors who worked on the Transbay Center or the contractors’ insurers.

Separately, the Transbay board also approved a $1.1 million payment to the homeowners of the Millennium Tower to replace a decorative 20-foot wall that construction crews had to rip out while they were building the new Transbay Transit Center.

San Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX-TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call (415) 777-8815, or email matierandross@sfchronicle.com. Twitter: @matierandross