Lounging on the New York subway with feet up on the seats was costly to lazy riders fined by the city last year, police said on Tuesday.

More than 7,000 riders on New York City subways were ticketed last year for putting feet on the seats or otherwise taking up too much space, under a law that makes bad manners a crime.

The offenses, which ranged from putting a bag on a seat to blocking a door to stretching out for a nap, carry $50 fines, police said.

In all, 7,373 riders were issued tickets in 2011 for being unable to confine themselves to a single seat. The law making such behavior illegal was passed seven years ago.

While the crimes may seem benign, the New York Police Department said enforcement has made the subway safer.

It is not unusual for police to find someone they have stopped for poor subway etiquette has an outstanding arrest warrant, said police spokesman Paul Browne.

"One of the reasons that crime in the subways has plummeted from almost 50 felony crimes a day in 1990 to only seven now is because the NYPD enforces violations large and small," he said in an email.

Police often encounter "armed or wanted felons who were initially engaged in relatively minor offenses, like putting their feet up, smoking, walking or riding between cars, or fare beating," he said.