Steam sale not cheaper than amazon sale for dues ex, etc.

hi everybody,
proof:
http://muslimgamer.com/steam-summer-sale-2012-day-2-prices-flash-deals-publisher-bundles-drm-metacritic-information/
[not sure if this info is accurate]
Also i was wondering if i can get steam keys and activate and download the game through steam for the following games:
sniper elite v2
civilization 5
deus ex?
thanks