How often do you check your receipts and when is the last time you caught a big error?

Admittedly I am not much of a receipt checker, however, yesterday I caught a huge error on a grocery purchase. A handful of fruits and veggies and lunch items came to over $42. When I got to my car and checked the receipt it turned out that the cashier had charged me for 27 Zucchini instead of 2. lol
A whopping $17.11 for 2 squash!

I think it’s time I start paying more attention to my receipts.