At a growing number of these businesses, owners are installing games of skill machines that people can play for cash prizes.
"They're actually getting pretty popular. Some of the stores I've been in you can see three or four or five people playing the games and then you go to the cashier for a payout," said Philadelphia Police Lt. Dennis Rosenbaum.
But the machines are also becoming quite popular with a ring of thieves.
Surveillance footage shows two or three men walking into the store. They walk over to the machines, knock them to the floor and then began smashing them with sledgehammers until they break open the money box and run off with the cash.
"It happens so fast, as you'll see in the video. They're out in a minute to a minute and a half, so they move with precision," said Rosenbaum.
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What's so blatant and alarming is that these smash and grab crimes are being committed while the stores are open for business with clerks and customers inside.
"It was very scary, they have a sledgehammer in their hand and they all put the scarf on their face like behind their masks," said store owner Satish Kumar.
"We don't allow cashiers to mess with them. It's unsafe for my employees and ourselves too and customers as well," Kumar added.
A growing number of stores are being targeted, particularly in the northeast section of Philadelphia. Police say some of those stores have been hit more than once.
"We have about two dozen jobs since October. Some of the stores have been hit multiple times. Like I said, they include these smaller convenient stores with the gas stations like Gulf and Sunoco," said Lt. Rosenbaum.
Authorities would like to catch this trio quickly before someone gets hurt. Anyone with any information is asked to call police.