Sure - it'd be nice if corporations brought us ad-free apps for free. But then, who is going to pay the salaries of those making the apps.
A lot of corporations give out their apps ad-free, for free. Look at the insurance apps (State Farm and Nationwide), banking apps (BoA, Chase), These are useful apps. But then they also interface with products that we've already paid for or services we already use, so these companies are making their money a different way.
All of the Google Apps & Evernote are free, as are many others. Just saying that they are out there, and some are quite good.
Here's the US Apps list, for those who asked - Since I'm typing it, i'm not going to include links or prices.
MLB.com At Bat 2009
BeejiveIM 3.0
Stanza
Instapaper Pro
E*Trade Mobile Pro
Pandora Radio
RjDj Album
AP Mobile
Brushes
Wunder Radio
Midomi Music Identifier
AOL Daily Finance
ColorSplash
Fandango
Ocarina
eBay Mobile
FlightTrack Pro
Lonely Planet Mandarin Phrasebook
Shazam
Dictionary.com
WeatherBug Elite
Tweetie
NYTimes
Photogene
Things
ESPN ScoreCenter
Loopt
Google Earth
Yelp