It could be some expenses formerly covered by the commision will magically pop up as separate charges.
From the October "Important Account Information You Need to Know" - a new section added to "Special Service Fees"
"Exchange Process Fee for ADRs - This is a fee Schwab charges to offset fees imposed on us by executing brokers. It is associated with transaction taxes assessed by certain governments as a percentage of the purchase amount on certain securities, and the rate is subject to change. The fee will appear as an "Exchange Process Fee" on your trade confirmation."
Note, Schwab does not say the fee is equal or limited to their actual expense.
In another new section, Schwab wants to make sure you understand that they are under no obligation to update any investment recommendation, financial advice, or financial plan Schwab might give you ...
By the way, when you get "free trades" from Vanguard, that includes waiving transaction fees on mutual fund trading, up to your limit. (Transaction fees, not Loads.)