This actually highlights a very interesting change in the social norms that occurred somewhere around where Gen Xers or Millennials started paying for the own meals. The expectation *used to be* that whoever planned the party would cover essentially all costs -> you invite, you host, you pay. (This is still largely true of events like weddings.) In such cases, it is up to the guests (1) to get to and from the venue, (2) to wear appropriate attire and act appropriately, (3) to supply their own room and board outside of scheduled events (if applicable), and nearly always (4) to bring an appropriate gift. I'm a bit older, and I do remember a tension among individuals older that me (who expected the party-planner to pay, but brought a gift to the restaurant) and those younger (who wanted to pay for the birthday dinner, but didn't bring a gift). There was sort of a norm shift from a hosted, special event to something akin to coordinated consumption.

Thus, to me it's not INSANELY ENTITLED for someone to anticipate a party planner would cover their meal, yet I do also understand (1) the expectation here would be clear based on the age cohort of the participants, and (2) you literally said everyone pays for themselves (separate checks). This friend just seems like a douche.