is there a legal way to consume alcohol bought at a store, outside of a home, hotel room, etc.?
I'm thinking in the U.S. and Canada. For example, if you're on vacation, you've checked out of your hotel room and have several hours until your flight, and you have some cans of beer left over. I know you could sneakily drink them in a park or something, but I'm just curious if there's any way to do it that's legal.
Yes, outside of Las Vegas, NV and The French Quarter, LA (other places noted below in comments, apparently). I don't know any place that allows it, but I could be wrong. I think it harkens back to the days of Prohibition with dry counties. Someone can correct me, as my history recollection isn't great. I'm guessing it's not much of a problem in the UK, or wherever you are located?
Like many laws in the US, it’s a hodgepodge of local, county and state regulations. As someone else here mentioned you can get one small city where you can drink legally in a park and in the neighboring town you technically can’t even drink on your porch. Problem with the latter situation is that not only is it ridiculous, but enforcement is likely to be unevenly centered on people of lower income or whoever the police happen to not like.
Cities such as Denver allow drinking in parks, but make the law difficult to follow - you have to be more than 50 feet from “any roadway, playground, recreation center, or swimming pool”. So I guess in the center of large parks only.
It really depends on the locale. It's largely divided between state and private land, but there's plenty of state land that it's legal to consume alcoholic beverages. I've been in many parks where it's legal.