IMDb's movie connections page for the episode states:
The Hunt for Red October (1990)
A shot of young Alec Baldwin is shown on the HD Camera monitor
Here's a frame from the movie with Baldwin in a similar suit:
It's the replica of the Royal Coat of Arms as part of a panel called Industries of the British Empire sculpted by Carl Paul Jennewein at the British Empire Building in Rockefeller Center, 620 5th Avenue.
I'm an American who has lived in Manhattan, and I don't know of anything unique about Midtown Manhattan that would make sense in this joke. Therefore, I think it's safe to conclude the line has no significance beyond the reference to Chinatown.
"Live Show", the fourth episode of the fifth season was shot in Studio 8H. From Wiki:
Studio 8H in the GE Building at 30 Rockefeller Plaza is where Saturday
Night Live (SNL) is filmed and was used as the location for "Live
"Live from Studio 6H", the nineteenth episode of the sixth season was also shot in Studio 8H. Again, from Wiki:
While it may not account for her use as a favorite word, Tina Fey based the character of Janis Ian (from her movie Mean Girls) on the singer Janis Ian, whose song, "At Seventeen," laments the social pains of not fitting in in high school. In the episode "The Breakup," Liz Lemon sings the song at a karaoke bar. The use of the number seventeen, then, could be ...
Ron and Liz are both cartoonishly passionate about food. Liz's relationship with food is a primary character trait. As goofy as 30 Rock is, it's striking how consistently Liz uses food as a defense or avoidance mechanism when faced with uncomfortable (usually romantic) issues. In season 2, episode 8 "Secrets and Lies," Jack tries to talk to Liz about his ...
I have not seen the show but the online transcript for that episode has the following:
Bless her heart. She had a hypoactive thyroid.
Do you remember the time she cannon-balled into Mel and Deschette's above-ground pool and tore the lining? And floated out into the street! And got hit by that car? I have never heard you laugh like that before! That's ...
There are no doubt a number of crossover similarities between the two shows. Some of them are outlined here.
Obviously, both of them worked on SNL at the same time and this no doubt led to the similarities between the two shows. Not sure specifically about the food posters, but if I were to guess, it is probably not a coincidence.