I agree with and have used the same options as CanuckFlyHigh for Banff and Lake Louise, and have never had any problems (including finding a spot in Banff) if you're willing to walk 5 minutes.

As for Calgary, I seem to recall street parking only being metered until 6pm, and then not starting again until 9am on Sat/ Sun (& Sun free in some cases). It just depends how much you hate paying for parking vs the looking/walking/ get up early enough hassle you're willing to deal with. Also FYI, the entrance to the Palliser where you pull up/ drop off is basically non-existent, you just stop curb side and it's generally a complete disaster (taxis double and triple parked, etc), especially if you arrive in rush hour. So again, depending on the time and how tired you are, you might just decide the valet is worth it! I generally fall in the 'hate paying for parking' camp, but here I was verrrryyyyy tempted...