IIRC, the greater Millis area has a high illegal alien population. The laws don't apply to them.
As of the census[9] of 2000, there were 7,902 people, 3,004 households, and 2,162 families residing in the town. The population density was 650.0 people per square mile (250.9/km²). There were 3,066 housing units at an average density of 252.2 per square mile (97.4/km²). The racial makeup of the town was 96.94% White, 0.71% African American, 0.14% Native American, 1.14% Asian, 0.24% from other races, and 0.84% from two or more races. Hispanic or Latino of any race were 0.94% of the population.
Source: Wikipedia