But most people agree that both weed and alcohol, regardless of how they fare relative to each other, have detrimental effects on the body, especially in the long term. Traveling, which you mentioned, especially by plane, does not carry these risks.
While your opinion obviously differs, I personally don't see why drugs are necessary to enjoy life. I don't smoke, drink, or use weed. I have many "problems" that others do not share - my job is tedious, I have always had difficulty making friends, never had a girlfriend, and my health has had setbacks. But I never have turned to drugs to get away from these issues. Instead, I take pleasure in the little things of life, like going for bike rides in state parks, playing Halo 4, and spending time with family over the upcoming holidays. It is unreasonable to think that everyone can be content with all or even most of their lives, because society cannot function without trash collectors and assembly line workers.
If you think life sucks, then it has always sucked and it certainly sucks less today than it did 100 years ago. As long as you have the basics of food, water, shelter, and medical care (which will now be available in just over a year), it is not necessary to use drugs to be content with life.