A guy is NOT going to "save" $1020, unless he doesn't win a game. But if he isn't betting the vig on top of the bet he will collect slightly more if/when he wins.
So rather than betting 100 and collecting 93.45, he will collect 96.15.
Plus they ARE NOT laying -104 on EVERY side. They are offering an 8 cent line in football. They are still adjusting the juice around. BIG difference. They could theoretically have a game -120/+112. Just allows them to move the holds and not adjust the line. Which can be better in the long run.
If they can hold the lines/spreads longer it doesn't matter how many middles you need to hit. If they NEVER move the line you (thebettor) will never get a shot at a middle there.
It also will help decreas their action on the heavy games somewhat as well. Especially if it is on a game with an oddball number. Who is going to lay -4 -120 when they can get -4.5 -107 somwhere else? I won't be surprised to see Pinny hold the line and show -130/140s this year. Obviously if youl ike the other side then you will be taking shots with the PLUS vig that way, especially if you can get a decent side shot on an early number.
I just don't like it all that much actually. When a book is offering the best holds around as it is, why do they feel the need to make them even better? I haven't heard of many people leaving them, so why do they need to entice even morepeople to bet with them.