>> I’m not sure what the point of supporting most small business retail is.
> 1) It's easier to influence a local business. "I don't like that you've stopped stocking X."
Doubtful. Businesses everywhere care about making money.
> 2) You may rely on the local business in some situations (urgently need something), but it can't survive on this type of custom alone.
The local part is true, although becoming less true with Amazon et. al. providing faster and faster shipping. The small part is either irrelevant or an anti-feature. Local big businesses typically carry more stuff, and hence are more likely to carry the thing you want.
I understand that there are small specialty retailers who carry goods big retailers might not, but that seems like a pretty niche case: needing something very rare right away.
> 3) The profits are much more likely to be fairly taxed and then spent in the local economy, which is positive for the community.
Probably not. If the difference in price is greater than the total tax collected, the community is better off buying as much as it can online.
I've yet to experience a small business that can keep its prices within 10% of Amazon.