I'm sure you could piece something together a little cheaper. A couple things to think about...
1. This is a direct chartered round trip flight out of Peoria. No direct commercial flights to Cancun from Peoria so you're looking at one or maybe two layovers each way on a commercial flight. I like the idea of no layovers.
2. I'd bet my mortgage that of your minimum 4 legs of a commercial international flight, during the busiest travel period of the year, during the current shitshow of pilot/crew shortages, that at least one of your legs is flat out cancelled or delayed to the point of missing a connection. I'd say there is a 50/50 chance you'll be spending the night in an airport if you make that trip commercially.
3. I hear most commercial flights make you pay for a carry-on or checked bags. I'd be shocked if the Bradley charter charges a bag fee. Savings of at least $60 right there.
4. You probably could find a cheaper flight out of ORD or MDW. However, I'm pretty sure Peoria has free parking. Savings of at least $150 in parking and gas plus five hours of car time. Even more savings if you got to get a hotel up in Chicago to make an early morning flight.
5. Looks like the Cancun Airport and the team hotel are about an hour drive apart. I'd guess that ground transportation is a minimum of $100 each way for those not on the team bus to the hotel. Savings of $200 right there.
6. Looking on the tournament website...looks like for me and my wife in a deluxe room it is $1,260 a person for 4 nights. That's $315 per person. That $315 is all-inclusive. I'm pretty sure I can eat $315 worth of shrimp tacos and drink $315 worth of Coronas alone each day.
7. And lastly...looks like the team plane will be home in time for Thanksgiving Day (albeit at 2am). A quick search online shows the earliest you could get to Peoria commercially from Cancun and still see both Bradley games is 2:15pm on Thanksgiving Day. I'm not sure about you guys, but I better be at my in-laws for turkey at 12pm or I'll never hear the end of it!