That has nothing to do with it.

The biggest concern is the speed of online play. If they took a 4 dollar drop every hand on a 1/2 NL game without a waiting list of 100 people Everyone's buy in will be gone within 2 hrs if not sooner.

At least in a B&M room the people who don't care about the rake don't see the money leaving the table rake wise all that fast.

At these online rooms the money will leave the table so fast in rake no one even the fish won't want to play.

It's also easier to see online what's on the table.

If 10 ppl buy in for 100 dollars and an hour later there is only 700 dollars on the table no one is going to play.

My exapmel is kind of extreme but 10 handed it's hard to count everyone's chips and figure out how much is leaving in rake.

Online that math takes 30 seconds.