Possible Clues:

• Tab taker
• Who provides money
• Word after "tax"
• Venmo user, maybe
• Who remunerates quiet philosopher?
• Single-___ (like a certain health care system)
• One putting money on the table
• In pair there's always one who foots the bill
• One taking care of the bill
• One of those in the cast left out - the one sorting out Bill