I'm seeing a few stores here and there which have a "round up to donate" option. I guess I'm a bit of a sucker and I always use that option. My groceries are always a round number as a result.

Ive always suspected that this is all of a tax dodge, a money spinner, and a pr exercise "we gave xxx to charity" - no, your customers did.

Just set up a direct debit to your favourite charity.