Liberty International Airport Marriott in Newark, New Jersey is a highly rated hotel that is willing to help out breastfeeding and breastpumping moms when they really need a private locakable space to express breastmilk.
All you have to do is ask the hotel desk staff and they will accommodate you to use one of their confernce rooms as a temporary space to feed breastfeed ro use your breastpump.
The seats are not padded, but still comfy enough, and better than using a hotel bathroom. Also there's a round table, and outlets where you could connect an electric breastpump.
This hotel has multiple confernce rooms in case one is occupied, but please politely ask before using them.