I see a few posts about this in the past year and a half, and it doesn't appear anybody has gotten a real answer. This does look like a bug.
In my case, I tried Removing Shares from one Schwab account I'm closing to a new one I just created. First I tried a "Transfer Shares" of all securities. It did successfully Add Shares for all securities in the new account, but it successfully Removed Shares for only about a third of the securities in the old account (thus a balance/value still showed in the old account when it should have been zero). A Remove Shares transaction did show for every security, but for two-thirds of them, the "share balance" remained what it was before, not zero as it showed in the successful removals.
And when I tried to Remove those remaining shares security by security, individually, whether the Share Balance went to zero was hit or miss.
So, I'm having a hard time actually zeroing out all the share balances in the old account. I guess I could go and delete all the old Buy transactions (as long as that doesn't wipe out cost bases), but it's … stupid that I have to do that, when you have the Remove Shares and Transfer Shares option.