​Houston Dynamo fans cheer as their team takes the field on Halloween night for a MLS playoff soccer match against the Montreal Impact on Thursday, Oct. 31, 2013, at BBVA Compass Stadium in Houston. ( Smiley N. Pool / Houston Chronicle ) (Photo by Smiley N. Pool/Houston Chronicle via Getty Images)Houston Chronicle via Getty ImagIf you wanted a sign of how universal Halloween celebrations have become in U.S. culture, you could look at this weekend’s Major League Soccer schedule.Saturday nights are the staple of the MLS regular season. Of the 15 games last weekend, 11 kicked off at 7:30 p.m. local time on Saturday night in their respective markets. There have been weekends when every single team is playing on Saturday night since the league struck its worldwide streaming deal with Apple TV.And yet that’s all changing with Halloween falling on Saturday night this week.When MLS schedule makers first saw this would happen, the league took the unusual step of asking home clubs if they would like to remain in the typical Saturday night window or choose another time to play their weekend fixture.According to a league spokesperson, all but the Colorado Rapids opted to move kickoff time rather than compete with trick-or-treating children and costumed partying adults. Eight chose to bump up games to Saturday afternoon, and five elected to push fixtures back to Sunday.In this regard, MLS isn’t completely alone. The National Hockey League is also playing slightly more matinees than is typical for a Saturday. But the college football schedule remains full of primetime games on Saturday night set to be shown on network TV, and the NBA will play most of its Saturday slate at night.And MLS’ clubs insisting on opting for a different path may be indicative both of the difference in the kind of fan likely to attend an MLS match, and the difference in how a team acts when the majority of its revenues come from fans attending games rather than TV contract revenue.MLS Matchday 34 ScheduleAll Times EasternSaturday, Oct. 311 p.m. | Charlotte FC vs. Orlando City2 p.m. | New York City FC vs. CF Montreal2 p.m. | FC Cincinnati vs. Philadelphia Union2 p.m. | Columbus Crew vs. D.C. United3 p.m. | St. Louis City vs. San Diego FC3 p.m. | Sporting Kansas City vs. FC Dallas5 p.m. | LA Galaxy vs. Austin FC5 p.m. | San Jose Earthquakes vs. Real Salt Lake9:30 p.m. | Colorado Rapids vs. Chicago FireSunday, Nov. 14:30 p.m. | Atlanta United vs. Toronto FC4:30 p.m. | Vancouver Whitecaps vs. Seattle Sounders4:30 p.m. | Nashville SC vs. New York Red Bulls7 p.m. | New England Revolution vs. Inter Miami8:30 p.m. | LAFC vs. Minnesota United9:45 p.m. | Portland Timbers vs. Houston DynamoAccording to a post on the league’s website this May, MLS has the youngest fanbase among the five North American pro men’s sports leagues, with an average age of 39.6. Put another way, MLS fans are most likely to have younger children, for whom Halloween is a treasured tradition. It’s also the leag