You can setup a different regular price for web store other than price in POS. For example, add shipping cost to web price.
2. Set the price difference for this attribute in Sku Info Tab, and click Save button to save Sku.
In this case, the regular price is $35.00, the web price adds $10.00. So the final web price will show $45.00. You can also set a negative amount to this box. Eg: if the web price adds -10.00, the final web price will show $25.00
Alternatively, to setup on sale online only, you can setup sale price with Web Store Only option: