Lots of people do things that are not legal or that we disapprove of or have different beliefs about or wouldn't do ourselves and if we cut off every friend who (for example) uses cocaine occasionally, gets drunk, speeds on an empty motorway, watches porn, doesn't boycott who we boycott, makes a cash payment to avoid VAT, doesn't re-cycle and uses huge quantities of disposable aluminium, and so on and so on, and we might not have any friends left.
Loads of people will do a little line or two at a party occasionally and not at any other time.
Light use doesn't give you a hangover or bad after effects. Hence its popularity, I suppose.
The people I know who are occasional; / social / party users are all mc professionals. Work in finance, creative industries, a hospital consultant, people in their 60s...
One friend, a doctor, uses small amounts as they believe it helps regulate attacks of severe depression "Systematic Review: Is There a Medicinal Use of Cocaine in Psychiatry?" by Andrew Troy Hodge, Robert Strayhan et al.
I stopped immediately many years ago when I read about women having their children held hostage to ensure they completed 'drug mule' trips. And that is the message I gave my Dc - all very woke in terms of fighting oppression. I have explained that social smoking of weed supports modern slavery in illegal hydroponic farms and is behind county lines and gang warfare in which people get shot and stabbed.