Use paper plates and cups.  They're only ~$.08-12 cents each.  You save money by not making your $50/hr employees wash dishes.  The sink will also be cleaner.  Put a recycling bin by the door to make it easier for people to throw their trash away.

Use a tablecloth for the table.  They’re ~$10 each.  You can wash them or replace them every month if they get too funky.

If the microwave users want a real plate, they can bring one from home and wash it themselves.  Eventually, if the microwave gets dirty enough, one of them will wash it.