Here is something I posted last year which breaks down why any bookmaker/Vegas/offshore does not want equal money wagered on both sides:
If a bankroll is sufficient - and we all know Vegas has a sufficient bankroll - why would a bookie move a number that has attracted a large amount of squares? Vegas views each game as one part of a larger series, forming the long run. The casino knows it will win ~50% of those imbalanced games and therefore it plays out mathematically just as though the casino had every game balanced.
The "equal action" way with a 2-game scenario:
$10,000 on Miami -6.5
$90,000 on UVA +6.5
Those who think Vegas wants equal money on both sides are suggesting that casinos will call off $80k of its action and "guarantee" itself $1k profit.
Game 2:
$10,000 on VT -6.5
$90,000 on UNC +6.5
They again suggest that casinos call off $80k to guarantee just $1k on vig of $10k. Thus, according to them, casinos have zero risk and guarantee a grand total profit of $2,000 of $220,000, a hold of 1%.
The real way it's done:
$10,000 on Miami -6.5
$90,000 on UVA +6.5
$10,000 on VT -6.5
$90,000 on UNC +6.5
The casino keeps it all, expecting to win 50% of the time, regardless how heavy or imbalanced the action is. It splits here, losing $79k on the UVA game and winning $89k on the VT game for a net profit of $10k of $220k, a net hold of 4.54%. 4.54% > 1%