The effects that a drug has on a person are not a consequence of its legality.
By Starbucks I assume you are referring to caffeine.
The effects of consuming coffee on behavior are, substantially different from those of consuming alcohol or marijuana or various recreational drugs. I don’t mean to suggest that caffeine “isn’t a drug”, as obviously it is.
But, yeah, people who drink a lot, often make some pretty questionable decisions?
So, while linguistically people might not tend to call an alcoholic a “drug user”, it still fits in the same kind of phenomenon?
If someone has a habit of recreationally shooting up heroine, I’m still going to regard them as a “drug user” even if they happen to be in a jurisdiction where their use of it is legal.
> unless you are going to start calling everyone in line at Starbucks a drug user too
Not OP, but I would call those people drug users, along with people who smoke tobacco and drink alcohol. Those are drugs, and people are ingesting them for their effects on the brain.
And that's fine, because drugs aren't bad, nor is using them (responsibly). I've used plenty, and I have a job and house and family, and my kids have never accidentally ingested anything apart from the time my 5 year old took a beer from a table during a party and drank half of it before anyone noticed.
The legality has absolutely zero impact on whether using the drug is abuse.
You shouldn't abuse any drug whatsoever, especially not when children are around. Using a drug to a point where it negatively effects the user or the people around him is abusing it.
If you are using a drug which significantly impairs your ability to make decision or, even worse, is spreading through the air, using it near children is abusing that drug.
I use marijuana. I follow advice and make good decisions. That's still true when intoxicated, even if the decision is "don't do anything you wouldn't do when sober."