The discounted prices are only reflected when added to the cart because of:
This Item has a Minimum Advertised Price (MAP) restriction set by the Manufacturer / Distributor that limits how we can display our selling price. The price above is our actual selling price.Below are the most popular lenses with discounts:
Canon EF 50mm f/1.4 - $339 (Reg $399)
Canon EF 85mm f/1.8 - $389 (Reg $419)
Canon EF 16-35mm f/2.8L II $1548 (Reg $1699)
Canon EF 70-200mm f/2.8L IS II - $2359 (Reg $2499)
Canon EF 70-300 f/4-5.6L IS - $1449 (Reg $1599)
Canon EF 100-400mm f/4.5-5.6L IS - $1559 (Reg $1699)
There are lots of other lenses at discount prices, just head over to B&H Photo.
*UPDATED*
Adorama and Amazon also has Canon lenses on sale:
Canon EF 50mm f/1.4 USM Standard AutoFocus Lens - Adorama | Amazon
Canon EF 85mm f/1.8 USM AutoFocus Telephoto Lens- Adorama | Amazon
Canon EF 16-35mm f/2.8L II USM Ultra Wide Angle Zoom Lens - Adorama | Amazon
Canon EF 70-200mm f/2.8L IS II USM AutoFocus Telephoto Zoom Lens - Adorama | Amazon
Canon EF 70-300mm f/4-5.6L IS USM UD Autofocus Telephoto Zoom Lens - Adorama | Amazon
Canon EF 100-400mm f/4.5-5.6L USM AutoFocus Image Stabilized Telephoto Zoom Lens with Hood & Tripod Mount - Adorama | Amazon