This is the problem of there being a disconnect between paying for travel and the act of travel with driving, so most drivers price (short) journeys as zero.
On the other hand, there is a lot of economic activity and tax generated due to motorists not considering the costs of their journeys. Make these costs explicit, or having to pay a train or bus fare and they won't travel. High streets will suffer even more if you start trying to price drivers off the road.
Amazon drivers will drive across the street, rather than walk, and it's not because they are delivering a heavy package.
Although there's evidence that typically those who walk or cycle can be more economically helpful to a high street than those who drive.
Very few people understand the total cost that they pay for car ownership in a year with the average being around £3,600 a year.
Even at half that rate, that's an average of around £5 a day.
If someone is doing 8,000 miles a year using a ICE they are likely spending over £1,100 in fuel.
It then doesn't take much to spend a further £700. Buy a £2,200 and run it for 4 years and sell it for £600 and that's £400, MOT is easily £60, insurance of £250 (although for most likely more).
That's already likely £1,800 or more.
That's without (say) £50 a year in parking and/or tolls and/or congestion charges (which could be spent over a fairly limited number of occasions), £70 a year (average) for tyres, £30 for bulbs, oil, screenwriter and other small value things. If brakes need doing or anything like that that can easily add more (even if you are doing it yourself and not accounting for your time).
As such it's easy for the costs to reach £2,550 a year (or £7 a day) and could mean that for some is actually better to catch the bus at £3 each way than drive.
That's still £1,000 below the average.
That also doesn't factor in the £20+ people may spend a month on gym membership when if they were being active as part of their day (walking more, cycling, etc) they may not need that.
For those who aren't paying £5+ a day, for a second car, it's easy to see how they could be able to spend more locally.
As for economic values, there's a big cost to society in being inactive and health issues from pollution (even if you want to ignore the environmental impacts cars have).
The reduction from the default speed in Wales from 30 to 20 saved more money to the government just in collision costs in the first year (actually it may have been as short as 4 to 6 months) than it cost to deliver - with that only considering that one factor and not any of the other benefits which may be delivered if people are more active.
It also has lead to Welsh car insurance prices being £50 a year lower (average cost).