Why do people giggle about, crack jokes about weed but not about beer?

Kids, teens and possibly adults laugh about weed, grin if it’s even mentioned, burst into laughter at a billboard reading, “Home Grown”, get into long conversations about it with anyone who will banter with them and basically act like it’s a huge part of their lives? What is the big joke? I never hear anyone giggling about beer or wine. They go to the liquor store and buy it with nary a laugh. Help me understand. Next they’ll have a tv show with people smoking it with thousands tuning in. I have nothing whatever against it ; just want to find out what the grins are all about. Why not just buy it and smoke it like drinking a beer?
If friends brought over a case of beer or bottle of bourbon I wouldn’t even think of cracking jokes. Ever hear anyone pointing to a billboard advertising Bud Light and laughing?