I have never once heard of a company made successful by cutting costs. Sure you can defer the death, but the death is still coming. You're just buying time.
There's no way you can compete with that, the people have voted that they would rather order many things online than go to the store for it. I don't care how much service you provide, but for 90% of the things I buy, being able to do it wherever I am and having it show up to my door is way better than going to try and find it.
I don't know if that would save many businesses, but it seems insane to me to take that one point where Amazon literally cannot compete on, and obliterate it.
Also, the information obtained from various online forums, reviews, websites and youtube could be more reliable and complete than from a salesperson. There are specialized products where a good salesperson can do wonders, but just not for much of retail.
I can't think of ever feeling this need. I can't really remember needing a salesman for anything besides charging me.
Start thinking more long term, and not just "how can I make a profit RIGHT NOW?!"