In May in the Forum, Ray Bersch pointed to a quote from Sunshine vs. Brett that seems to apply here:

"In 2014 the Maine Supreme Judicial Court in Sunshine v Brett in a footnote opined that “Consideration of the type and frequency of use of the private road is entirely appropriate in determining a fair and equitable method of allocating the costs associated with maintaining the road.”

I suggest approaching this subject with caution. We have an owner whose property is primarily used for short-term rental --lots of transient traffic that does not often obey speed control signs and rope speed bumps. They would not be happy if we charged them extra. We have also not dealt with "second dwelling units" over the garage, etc. Good Luck

I suggest the excessive use be easily identified as "flagrant" backed up by your by-laws in case your extra fee is contested in court. Perhaps compiling some sort of "proof" of extra usage --photos, logs, etc.