Tipping on the Receipts - 18 or 20%, Tacky?

[lat]

We just got back and I felt a bit forced to tip the wait staff 20% because on the receipt at sit down restaurants, it shows the amount for both 18% and 20% tip amounts. It made me feel that I shouldn't give 15%, and would make me feel bad to give 18%, so I ended up giving 20% each time. Do you feel a bit forced, or was it just me?

 

[TDC Nala]

Tipping questions should be addressed on the Tipping Info thread:

http://www.disboards.com/showthread.php?t=1870320