Originally Posted by
reft
2) Checkdigit your tip. Leave a tip that causes the restaurant bill to add to a funny number. Examples: on a $60.00 bill, make the bill total $70.07; for a $70.00 bill, it would be $82.68 - the tip you add makes the first digit in the total match the last digit in the bill total. Or make the total a numerical palindrome ($82.28), or something else that rocks your world.
This will stick out on your statement, and if you have to make a chargeback claim with the credit issuer, you can tell them what you do, and why this charge is not like all the rest of your historical restaurant bills.
I've rounded all my restaurant bills to even dollar amounts for at least a decade. When I scroll through my statement, if I see a restaurant charge that's not an even dollar amount, I go looking for the slip. Far and away the most common discrepancy is that I'll leave a tip of say $5.32 and the waiter will enter it as $5. Occasionally, they'll forget to enter it altogether and stiff themselves.
I've had a couple times where the restaurant messed it up--one was probably a typo, but they 'couldn't find it', so they got a chargeback for the difference. The other was definitely someone trying to steal; the bill was less than $20 and they left themselves a tip of $20 even. I couldn't find the slip, but pointing out my rounding habit actually convinced my local credit union to pursue it. They ended up reversing the whole charge, so there is such a thing as a free lunch.