This is basically the value prop for mom n pop shops. If the salesperson is also the owner, they have a lot more incentive to get to know you and steer you towards the things that will be best for you, in order to
1) keep you coming back
2) navigate highly localized politics
Mom n Pop shops are great but getting rid of ads doesn't put the genie back in the bottle when it comes to big box stores and Amazon. It also doesn't solve the shelf space problem. I've found incredibly niche and useful things through online retail ads that a local business would be insane to stock because they would have dead inventory.
1) keep you coming back 2) navigate highly localized politics