If you're like me and keep buying your games since the past three years or so exclusively on-line (except for console games, for either new or old consoles) then you will most likely be able to wait until their prices go down a bit before buying them, if you're patient enough of course. Buying games retail for the PC, for me, is something of the past, with Steam, D2D and GoG, and being able to buy CD Keys only (DirectGameKeys for instance) I am usually able to save up to 50% in prices per game, depending on how long I wait before buying them or depending on what special deals I can find for them, or a combination of both.
I've bought a very few brand new games on-line at full release price, namely Empire: Total War, Dragon Age: Origins DDE and Mass Effect 2 DDE, those three games are the three exceptions since the past three years or so, all other games I've bought were reduced in prices after some time, or during special deals (week-end deals, anniversaries, etc.).
There are absolutely no ways that retail games and retailers would reduce the game prices as fast, as often and as low as it occurs on-line with Steam, D2D, GoG, DGC and a few others, which is also one big advantage over retail purchases, and when you've got nothing to hide, when you buy things legitimately and when your OS isn't filled with crappy software all over the place chances are that almost any type of DRM won't cause a single problem. Most games I've bought for the PC were around $30, sometimes I can find deals at one place when the game is still at "full price" somewhere else, sometimes you only need to check around too.
So, to conclude, I wouldn't say that PC games prices are "lower" per se, I mean at least at release and the following few weeks or months, but with digital purchases there are many ways to legitimately circumvent full retail prices and end up spending much less money than for console gaming or for brand new retail PC games.
