I've heard the same thing here a bit as well, but there are a few extra considerations some people have mentioned and often don't seem to mention. From what I can gather, a village should be atmost 1 day away from another village, but that doesn't mean that the other village is in your direction of travel or that there will be a road of villages all 1 day away from each other all connecting all the major cities together.
Firstly, you still need the resources available to form the town in the first place. Otherwise, it would be heavily dependent on trade, but that's for the next point. You would need a source of fresh water and land to grow food as well as wood/stone to be able to build buildings. If a place doesn't fulfill these conditions, chances are a village won't form. If a location isn't able to provide food and shelter, chances are people won't settle down there.
Now if you don't have your necessary resources, the only way to get them, is by trading. To build a village dependent on trading means you have one of two things. Either a very valuable good, e.g. Gold, which other people really want and hence they will be willing to trade or invest in the village to gain access to the resource. The next option is there is very large amounts of traffic that have to travel a far distance, and hence you can rely on a constant flow of incoming an outgoing people/traders to keep your village well supplied and stocked up.
So if you have 2 villages that are both in ideal locations, but say there is a mountain, desert or forest between them, it is plausible that there would be no village/town between them, because the location between them would be very hard to settle and not provide much benefits to those who do.
Also if your villages are on the frontier, or the kingdom is currently expanding and settling new villages, its plausible for them to be spread out and placed in perfect locations, rather than only 1 day away. This way, the earlier settlers get better resources, and later on, once they are more developed the areas between will be settled and safer travel paths will be opened up.