The Tip Opt-Out Protocol
High-Signal Summary
Tipping is voluntary. If a user opts out, their tip liability becomes $0.00. The total tip amount is preserved: the opted-out user's would-be tip share is redistributed equally among the remaining "active tippers".
Why This Matters
Social pressure often forces non-tippers to pay, or forces one person to cover the gap. HackBill formalizes the "Opt-Out" as a mathematical operation, removing the social friction.
The Redistribution Rule: When User A opts out, their "forfeited tip" (what they would have paid proportionally) is divided equally among all remaining tip-payers. This ensures the total tip amount is always preserved.
The Decision Logic
User toggles "Tip Opt-Out" = TRUE
User Tip Share = 0.00
Tip Percentage = Total Tip / Bill Subtotal
Base Tip (each) = User Subtotal * Tip Percentage
Forfeited Tip = Sum(Base Tip of all Opt-Out Users)
Redistribution = Forfeited Tip / Count(Tip Payers)
Final Tip = Base Tip + Redistribution