They don't need a web page if 90% of their customer base knows who they are and the 10% that doesn't still uses yellow pages.

I would really want to know how much business would some car mechanic in pleasantville missouri would see from having a web page.

Having a site with work hours, phone number, and current address helps in Google Maps. You can also add a "sign up for updates and coupons" thingy and at least some people will sign up. If it's cheap to setup, might as well do it.

In particular with car mechanic I would like to know the cost of basic services like tire rotation. I know it's $20-$30 at a major brandname, but I could use a local shop so I don't have to drive out of my way. Some car dealers service departments now have online services to schedule appointments and such, I think half of that can be repurposed for a small car mechanic shop as well.

There are two ways to run a business after it reaches some profitability: always optimizing or just kicking back and relaxing. Some people are happy with just their Facebook page and others would optimize and increase sales further by funneling people in through Google Maps.

(This is why I've taken photos of some restaurants in Google Maps and posted them; they aren't doing any advertising on their own so it's nice to help them along and get more visitors).

I don't really disagree and a Facebook page is probably a lot better than nothing. I would note that SquareSpace seems to do a good business (assuming that's a reasonable conclusion to draw from the amount of advertising they do) so there does seem to be a market for simple template-driven websites.

(on the other hand, given they advertise a lot on podcasts and the like, they may not be targeting traditional local businesses.)

I think they're mostly targeting the people those local businesses ask for assistance with those ads, to be frank :)

You'd be surprised. There's more customer using the internet than businesses investing in it across many niches. I launched a trades business with my brothers and thanks to seo and social we've grown a real, substantial business. We launched the site and marketing before we bought the equipment. We acquired over 150 accounts in the first two years (businesses paying thousands per year). Phone just keeps ringing now.

I think in part this to me, shows that sometimes, small businesses don't think about long term planning. Being on the web, having a real web presence as others have mentioned, from both having a website, a facebook/instagram/twitter/yelp page (not saying all of those, just examples) to doing advertising on the web (which when done properly, is better ROI at a cost that most small businesses can afford, than say a single billboard perhaps). Thats just not meeting your customers where they are, and sometimes that means future and not existing customers.

Its a lot to take in, to be sure, but you can't beat the scale of the internet for getting your message out.