Let's get this out of the way first: 49ers coach Jim Harbaugh was absolutely right to decline a penalty resulting in a safety toward the end of his team's win over the Seahawks. With a flag for a chop block, San Francisco could have accepted it, taken two points to push its lead to nine, and received the free kick. Instead, Harbaugh chose the result of the play on the field: a fourth-down pass to Ben Obomanu than came up just short of the first-down marker. Turnover on downs, Niners kneeldown.
This was more than just patented Jim Harbaugh trolling. Though the conventional wisdom says "take the points, make it a two-possession game, there was really nothing for San Francisco to gain." It's not even so much that there was any realistic chance of Seattle recovering their onside kick (yes, you can kick onside after a safety), scoring, recovering another onside kick, and scoring again, all within 43 seconds. Why expose your "hands team" to an onside kick, risking an injury to a skill position? If you have the option to end a game without running any more plays, and Joe Pisarcik isn't in the building, take it. Points be damned.
(Net points is the seventh tiebreaker for divisional standings. The season coming down to those two points is less likely than the Seahawks coming back to win last night.)
Now, about those two points: They were the difference between the 49ers winning by seven, or by nine. That matters to a not-insignificant subset of viewers—those who had money on the game. Depending on where you wager, Seattle was getting 7, 7.5, or 8.
R.J. Bell of Pregame.com breaks down who got hosed, and for how much:
49ers -7 had money refunded (but would have won with the safety)
49ers -7.5 or -8 lost (but would have won with the safety)
Seahawks +7 had money refunded (but would have lost with the safety)
Seahawks +7.5 or +8 won (but would have lost with the safety)
Overall, it's safe to say that coach Harbaugh's unconventional decision resulted in a $75 million dollar swing worldwide with the bettors overall losing that amount (due to 65% of the action being on the 49ers) and the bookies overall winning that amount.
I'm going to try to make anyone who lost money feel a little better (though it's not going to work). The chop block penalty on Paul McQuistan? A terrible call that shouldn't have been flagged in the first place.