How did you like living in Cambodia, and which city did you live in?
As for Laos, you must note that almost all stores and shops close between 21 and 22.00. I never really found the reason for this. Even in the Capital, Vientiane, it was only the bars that were open after 22.00. At times it was nice and peaceful, but at other times arriving late to a city, or wanting something to eat sucked if everything was closed.
As for hitching i found Laos quite easy. Waited no more then 10 - 20 min, despite the few cars there are in this country. Most people drive pick-ups so be prepared for alot of wind and sun!