The configuration and history of your roads may be significant. For example, if there was originally just one road that formed a road association, and later a second road was built off the end of the first road, a statutory road association would have to include the owners on the second road as members because they use the first road for access; however, the members of the original association would not be compelled to contribute to the maintenance of the second road, which they do not use and which was not part of the agreement when the road association was formed.
On the other hand, if the second road were to join the first road near its beginning so that owners on the second road use very little of the first road in order to access their property, it would seem unfair to make them pay the same as those who use the whole first road, while not getting their own road maintained.
A very different scenario would be if both roads were built at about the same time, and a road association was formed to cover both roads from the outset. In that case, I would think that funds raised should be used to maintain both roads equitably.
Yet another factor to consider would be if both roads are in essentially the same condition or not. If one road was brought close to town road standard by the developer but the other was not, it could seem unfair to force the members on the better built road to pour more funds into the worse one to try to bring it up to standard. On the other hand, since those on the second road are contributing to maintenance of the first road, it may seem perfectly fair for those on the first road to contribute to maintenance of the second. It also may depend on how much it feels like one community. If there is good rapport between members, people on the better built road may think it's the right and neighborly thing to do to see that everyone has decent access. I think it boils down to what is fair in each individual situation. Try putting yourself in the shoes of each member and see how things look from there.
As for the Town taking over maintenance of one road and not the other, I must comment that I've seen few towns that are willing to take over maintenance of any new roads unless they are first brought to full town road standard at private expense (if then). So if one road meets that standard and the other does not, that would justify the town only accepting one of the two.