Last week, about 120 diners, who had consumed about 2,000 euros of food and drink, left a restaurant in northern Spain as dessert was due to be served.
It has now emerged a second restaurant only 10km (six miles) away was previously targeted in the same way.
The owners said they believed they were the victims of the same group.
In the first case, the group, purporting to be celebrating a baptism, paid a deposit of €900 ($950; £770) to eat at the El Carmen restaurant in Bembibre, in the north-western Castile and Leon region.
"It happened in the space of a minute," owner Antonio Rodriguez said. "It was something they had planned and they left in a stampede."
El Carmen's case felt more than a little familiar to Laura Arias, the owner of El Rincon de Pepin, a restaurant in nearby Ponferrada.
The group told her they were celebrating a wedding, she said, and ordered a fairly basic menu. They paid €1,000 as a deposit, but consumed €10,000 ($10,600; £8,600) worth of food and drink.
"There were 160 of them and they all disappeared. Suddenly. Within five minutes," Laura told the BBC. "That was the unusual thing.
"Usually people leave over time, and you expect someone to come to talk to you and say they will settle the bill the next morning or something. But they didn't say anything, they just disappeared."
The unusual crime has been reported to police, but Ms Arias is in no doubt who is responsible.
"It's the same people. We can tell from the photos." Reports in northern Spain quoted witnesses as saying the group was from eastern Europe.
On Monday, the Diario del Leon newspaper reported (in Spanish) that two ringleaders had been identified and that police were working to establish firm links between the two cases.
Police are investigating whether a gang who ate thousands of euros of food in a restaurant in Spain before fleeing had targeted another eatery.