[winflop]

I understand that a point spread is intended to produce roughly 50 percent betting on one side and 50 percent on the others. But I don't really know what the intent is when somebody is established as, say, a 5-1 shot to be national champion.

Casinos can also manipulate the amount you are paid on one side of the bet or the other - it's not always a dollar for dollar payout.  This is often done with individual football & basketball games where there is a point spread.  For baseball it's simply a variance in payout there is no run spread afaik.

[winflop]

I understand that a point spread is intended to produce roughly 50 percent betting on one side and 50 percent on the others. But I don't really know what the intent is when somebody is established as, say, a 5-1 shot to be national champion.

Casinos can also manipulate the amount you are paid on one side of the bet or the other - it's not always a dollar for dollar payout.  This is often done with individual football & basketball games where there is a point spread.  For baseball it's simply a variance in payout there is no run spread afaik.