My parents did the same; both my childhood dogs were fed Pedigree then Beneful. They only went to the vet for vaccines (except for when my parents paid for ACL surgery/bone spur removal on both knees for Baby when she was about 12 - she was a GSD/husky mix that lived to be 17 - and had one knee surgery for Lucky - GSD/who know what else mix that lived to 15). I like to call my mom Snow White and/or the Animal Whisperer; I've never seen an animal not flock to her and love her and every pet she's ever had lived ridiculously long. She had 2 separate cats that lived to be over 20 years old, were partially outdoor cats, were fed Alpo and Meow Mix and never went to the vet.
Ralphie - GSD, rescue, Gotcha Day 2/10/13
Nightshade - born 6/3/2003 - Domestic medium hair/Maine Coon mix (feline)
James - Domestic short hair (feline), rescue, Gotcha Day 6/23/11