Joseph,
Please define the Tekanah, which category of Minhag is it based upon – is it based on Halacha or סייג?
If its non of the above then it has no status of a “minhag”.
However, as mentioned above it could be a Tzenius based issue of Das Yehudis if its a place were driving is considered strictly a male’ act or not beKavodik . To have a better understanding, there are places ( by Chassidim) where a Rabbi/Rebbe will not drive a car. I heard from someone this is the case in Williamsburg and Kiryat Joel that most that call themselves Rebbes/Rabbis i.e. there do not drive.
Whereas, in the Yeshivish world every Rosh Yeshivah and their wives drive.
Hence, the Rabbanim in lets say KJ and New Squire (where there is one Bes Din etc) can say to all their Kehillah members that the above is considered within our community as Lo Tilbash and not Tznius etc. But I doubt this will be MeChayev anyone else who passes by to have to abide.
Also, once the status changes and somehow starts becoming the norm (whatever reason involved) it automatically has no basis.