Possible Clues:

• "I'll take care of this round" ... or a hint to 50-Across, 4-Down and 10-Down
• "I'm paying for this round!" ... or a literal interpretation of 16-, 23-, 49- and 59-Across
• Remark from one who gets a round
• 'I've got this round!' ... or a literal hint to this puzzle's theme