Here is what Eastern Warrior is trying to explain to you. Let's take your example. Say you want to buy XYZ at 25.75. You believe this is a great trade and it's certainly going to 35.00 in a few weeks after earnings. So you bid for it at 25.75 and your buddy does the same using his IB account. The stock trades down to 25.75. It trades a LOT there. But you are the very LAST guy in the stack because that's what Robin Hood does. Your buddy gets filled and you don't. It doesn't trade all the way through. The stock sure enough goes to 35.00 in two weeks just like you predicted. Your buddy makes 9.25 per share, you make nothing. All because you wanted to save the equivalent of a penny per share. So technically your buddy didn't make 9.25. He made 9.23 after paying his commish to get in and out. You made NOTHING. Now, you might think this is not a big deal. I can tell you as someone who does this for a living that missing trades is a HUGE deal. I could give two shits about saving pennies when I'm trying to make 10 dollars. You will ALWAYS be at the bottom of the order stack. Now, most of the time this won't be an issue. But if you miss just one trade a year, it will wipe out all the savings and then some from the pennies you are saving. Just one trade and the economics go out the window.
Since I trade in small amounts of shares... usually between 30-500 I don't mind being at the bottom of the order stack...now if I traded in the thousands of shares then maybe this would be a huge huge problem for me but in actuality it's not...so I'll continue to stick with the free trading platform....out of the 4 trading accounts I use the one with the highest commissions I haven't made a single trade on...the broker in the middle range cost I have traded a couple of dozen times but the free trading account I have made approximately 185 trades since February!!!
Compared to my highest priced account I have saved $1,275+ worth of commissions so far in 2018!!!!!!!!!!!