When we hosted several parties when each of our kids graduated. We insisted on paying though others did offer. We live 2500+ miles from venue. Some folks flew in, some drove. We hosted a 70th bday party for DH as well at one of the grad events.
We chose venues we knew we could afford but guests were polite and didn’t choose to have multiple alcoholic beverages apiece.
We had a nice mid-Eastern restaurant with a buffet for one meal, a lunch on campus at a nice restaurant for another, a Thai dinner for another, and perhaps a few other things I can no longer recall. I only kept the happy memories.