Restaurant purchases authorize for 10% more than the purchase to cover any possible tips that may come in with the final settled transaction.
For example, you may have only purchased $20.00 at Joe's Restaurant. However, when you see the pending transaction in your Bento account, you'll notice that it shows a pending transaction for $22.00 at Joe's restaurant. This is to account for the possibility of a tip that may come through when the merchant sends the final settled transaction.
When the pending transaction comes in for the final settled amount of $20.00 the pending transaction of $22.00 will release and you will only be charged for the final settlement of $20.00 at Joe's Restaurant.
Please keep this in mind when setting employee limits as if the employee doesn't have enough in their available spend to cover both the restaurant purchase + the 10% they may get a decline if it exceeds their spend limit.