Is there any disadvantage to the casino by letting players bet multiple spots at the same amount at blackjack?

I would like to know if it is a disadvantage for casinos to allow players that are playing multiple hands at blackjack to make equal bets. For example. A player is playing 3 spots at table max. Table max is $100. He is betting $100 $100 $100. Does this create a disadvantage to the casino as apposed to letting them bet progressivly?