It's better to make a fiver of profit per customer on 50 customers per day than to make £2.50 profit on 75 customers. It's elasticity of demand. No point in halving your profit per customers unless you can far more than double your number of customers buying the same thing.
That is a very good point. A lot of people - including many of the business owners themselves - see a high footfall and turnover and assume that it must equal success; but this is not necessarily the case.
I remember reading a book some years ago about the Wal-Mart effect and one business sticks in my mind: an American micro-business that made expensive, top-quality lawnmowers. Their reputation and popularity grew and eventually, Wal-Mart got wind of them and got them 'into their fold'.
Instead of selling a handful of mowers a year, as before, they were now moving hundreds of them; but because of WM's demand that they not only set the retail price - which they insisted be more in line with the other cheaper, factory-assembled, brands - but also that costs be reduced by 5% every year, they found that they were shifting loads and loads of units, but struggling to make any profit at all, whereas before they'd done quite nicely for a small family business. It's a sobering thought that many people just don't want to take on board that you can be rushed-off-your-feet busy and still not make any money, or even lose money.
Also, the fact that everybody now associated them with WM meant that they were perceived as just any old lawnmowers, rather than the highly premium product that they were, so they couldn't even withdraw from the deal and go it alone again, as their brand was now irreparably tarnished.
I think there's definitely a place for small-scale businesses whose owners are not interested in growing any more than necessary. Maybe they figure that, if they can make a reasonable living by opening limited hours and serving a restricted number of customers, the work/life balance is worth more to them than doubling their income but also doubling their workload and hours that they have to commit to the business. Not really that different from 9-5 M-F employees, most of whom could take a second job in the evenings to increase their earnings, but most of whom figure that they earn (and work) enough and so don't.
All 100% well and good, just as long as you cheerfully accept that and don't start lashing out at people for not being able/willing to slot into your self-imposed confines in order to increase your income without impacting at all on the hours that you're willing to work.