The moment
A small bowl of mints, a few tea bags, or a predictable salty snack tells people someone thought about the evening.
A useful detail
Choose things that travel well and do not create a huge cleanup project. The snack is support, not a centerpiece.
Keep it human
If food is complicated for the group, skip it. A water pitcher and a welcome are still hospitality.
Let the person be the point.
A gift is optional; a sales link never replaces a useful gesture.