What they were wearing was modest brown costumes, presumably made of skins, with a hint of Maya style. This is about what I'd expect your average ancient Maya to wear. Not a peasant's loincloth or an emperor's robe, but something in-between. Something plain and nondescript.
Based on all the above, this would've been an excellent skit about Indians. But two jokes brought it back down to mediocrity.
I believe the Maya used a base 20 system for their calendar. Presumably they knew their own number system by heart, so the new calendar wouldn't have been difficult for them.
It's pure Eurocentrism to imply our calendar is simple and sensible while theirs was needlessly and foolishly complex. I suspect it isn't even true. Suppose you have to meet someone in eight weeks or eighty days. Can you state the meeting date off the top of you head? Without looking at a calendar, that is, or doing a few minutes of calculations? Under a base 20 system, coming up with the date would be easy.
Sacrifice in Maya culture
Animal sacrifice and bloodletting were a common feature in many Maya festivals and regular rituals. Human sacrifice was far less common, being tied to events such as ill fortune, warfare and the consecration of new leaders or temples. The practice was also far less common than in the neighboring Aztec societies. The Maya people would sacrifice their prisoners. The prisoners were most often from neighboring tribes.
Yes, it's possible the Maya did sacrifice a few virgins. If so, the practice doesn't come close to representing the whole culture. It's more of an exception than a rule.
So Saturday Night Live portrayed the Maya as normal, good-humored, and inventive...then undercut it by ending on the human sacrifice note. Takeaway message: the Maya were bloody barbarians who made weird stone calendars and murdered people. A skit that could've been great ended up being merely okay.
Still, it was a nice try, and perhaps better than anything SNL has done featuring Indians. Keep it up and don't lapse into obvious stereotypes, people.
For more on Saturday Night Live, see Columbus Day in Saturday Night Live and Taboo in Saturday Night Live.