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 monthlyevery 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.