Here's an article by Bernd "Thumb" which tells of his cycle hitching journeys:
Cycle Hitching (or On Your Bike?).
Other digihitchers have done this too, Espi from the Netherlands cycle-hitched around Canada and got some great lifts.
A friend of mine from Germany rode from San Diego to Las Vegas and was repeatedly asked if he needed/wanted a lift by passing motorists.
When I was living in Egypt I went for a ride with a couple of friends along the Suez Canal. One of my friends got so tired that he couldn't keep going so he caught a ride with a taxi. That's not hitching but it shows that it's not a problem to get lifts with your bike.