Yes Lowes does charge you for dishwasher installation so you'll have to pay the installer for the dishwasher installation from Lowes.
Lowes will hire independent contractors to install your dishwasher and you may need a new valve or some other plumbing to install the dishwasher.
If your house has never had a dishwasher in the house then you will need additional plumbing installed to allow the dishwasher installation.
So you'll usually be billed by the independent contractor for the installation of the dishwasher but sometimes lowes may bill you and then pay the contractor.
When Lowes installs appliances or other things in your home they usually hire out independent contractors to do the job.