I think you are mistaking yuppie and hippie. Yuppies are not the pot smoking types.
There are a bunch of homeless pot addicts roaming the streets now that pot is legal? legal weed is not cheap at all. The taxes are very high, and it is a cash only business. Do you think marijuana is so addicting that if homeless you would cross the country to go to a place where it is legal? That shows an awful lot of initiative to smoke super expensive weed, when it is available everywhere else for very cheap. That also seems to fail to account for the fact that many homeless have mental health issues, and addictions to way more serious drugs than pot.