Saying the offer isn't negotiable but oh hey, I got your email about offer from XYZ and we'd like to bump our (lowball) offer. Saying they'd like to "chat" ins

Saying the offer isn't negotiable but oh hey, I got your email about offer from XYZ and we'd like to bump our (lowball) offer. Saying they'd like to "chat" instead of just telling you you passed the interview and got an offer.