Sales tax collected is neither income nor expense - therefore, will not show on a Profit and Loss Report.
You collect sales tax from your customers and hold it (as a liability) until which time you remit it to the tax agency.
Why would it be 'better for you' to see it on the P & L?
In my experience, the Income/Sales from customers on a sales tax report is the total amount prior to the tax collected. Then, the tax is calculated on the form and should, in theory, match the amount that you collected from your customers. If you are using the sales tax platform in QuickBooks, this should match the sales tax liability report.