Can you allow Tip Amount to be Greater then Cart#882

Right now you cannot enter a tip greater than the Cart amount. Why that limitation? Especially with delivery that limitation may not be appropriate.
For example, our client who just added the Captain delivery told us they have a regular customer who orders an $5 appetizer every day for lunch delivery and gives a $10 tip to keep the driver motivated, and his total bill is over $25. (he also orders larger amounts for dinner etc). Please consider lifting this limitation. Thanks.

Its a limitation because it opens more posibilities for abuse and is used in fraud prevention features.