Family Dollar review: didn't know what a manufacturer coupons were

So I went to family dollar to do some shopping on Saturday afternoon...upon checking out I reached for my coupons & handed them to the cashier he placed them on the counter...he never scanned them...I said yall don't keep the coupons he said no...so I put back in my purse & proceeded to go to my truck something said check your receipt & to my susprise he never scanned them...so now I gotta go back in the store get back in line & wait for him to get to me & I say you never scanned my coupons he looked @ me like what was coupons I said do you know what these are he said no...really & you work in a store that takes them...so I asked the other cashier do you know how to do coupons he said yes...but I had to go to my truck & retrieve my items so he can return & resale the items back so I can get my refund...much to my problem I was late for my appointment due to your cashier not knowing what a coupon was & standing back in line on a nice Saturday afternoon...