I spent June in New York and Washington and was surprised to see some signs of rugby. A few pubs playing MLR. MLR games on free to air (I think) TV. A few MLR Jerseys on the streets. There was also All Blacks, Springboks, England gear about, no doubt being worn by expats.
The game does exist over there, but it was perfectly portrayed by one local who walked past a screen playing MLR in a pub, watched 30 seconds before saying 'ahh we already have football' and walking over to a screen playing the Mets.