My parish ordinarily celebrates a weekday noon Mass. That time slot seems less than optimal for a civic holiday like Labor Day. It’s one of three days of the year in which we move 12:00 liturgy for a non-holy day to 9AM (along with Memorial Day and Thanksgiving).
For you parishes that celebrate a noon or evening weekday Mass, do you maintain the schedule for a day like this coming Monday?
Also: do you use the weekday reading or employ the votive Mass appropriate to the theme?
For Catholics outside the US, any interesting practices for civic holidays in your nation?
Catholic Sensibility 
For Thanksgiving, my parish and almost all around here (Philadelphia) use the special votive Mass for that day. For Memorial and Labor Days, and July 4, not 100 percent sure.
And the general rule for my parish and others around here is you either maintain one morning Mass (for example, 8 AM) or do one Mass at a special time, such as 9 AM. From my observations, the 9 AM Mass on civic holidays seems pretty popular in a lot of places. I know St. Francis of Assisi in New York (the one near Penn Station) has an 11 AM Mass on the summer civic holidays and on Thanksgiving, and more Masses (usually one each in the early morning, midday and late afternoon) on the winter civic holidays (Martin Luther King and Presidents’ Days) and also on the Friday after Thanksgiving (which, while not official, is pretty much a work holiday in these parts).