Commuters at Penn Station are wondering where the slew of longstanding fast-food chain restaurants there have gone.

Kyle Soto was stumped Friday when he approached the wall of plyboard covering the space that was until recently occupied by TGI Fridays, KFC and Nathan's.

"I came here for pizza and magazines while I was waiting for the train," he said.

All that was left of the stores was a lock and an alteration notice from the buildings department.

Commuter Gregory Johnson said, "I'm trying to figure out what's going on. Why no warning or anything?"

"This is not Penn Station without these stores open," said Christine Preis of Merrick.

Commuters wondered if the businesses were kicked out by Penn Station retail space owner Vornado Realty Trust. Neither Vornado nor the restaurants' owner, Riese Corporation, returned calls Friday, but MTA board member Mitchell Pally said the reality is not nearly as controversial.

He said it's all part of a remodel -- a push to bring more upscale retail to Penn Station, similar to businesses found in Grand Central Terminal. There could be a raw bar, for instance, or a bookstore and wine store.

Preis said, "That would be nice, anything to improve our commute."

But another commuter said the renovations are unnecessary.

"They have everything. It used to be seedy," he said. "They've fixed it up enough."

It's not clear when or if the stores will reopen. In the meantime, the MTA said it's been looking at ways to improve Penn Station and its real estate offerings.