https://www.urbandictionary.com/define.php?term=cahuenga principle

The Cahuenga Principle states that a tip should be no less than half the value of free drinks (or food) recieved.

I just tip the amount I would have tipped if it was something paid. In practice that only happens to me in bars if the bartender gives me a drink on the house and I’ll always tip in those situations. Always tip your bartender :)

Don’t? It’s a gift. Why tip? If they expect you to then that’s hypocrisy on their part.

The expectations will probably be different between cultures but personally, nothing. It’s a gift after all, giving them money for it would make it a business transaction. Of course, when there’s an opportunity, I’d give out some food or drinks to my friends as well.

When I’m given free stuff I tip as if I paid for it. So if part of a meal is comped, for example, I’ll use the original subtotal, pre-discount, to figure out what to tip.

If I’m only getting drinks (coffee, alcohol etc.) I default to a $1 tip per drink, and if given a free drink I’ll add on to that while factoring the cost of what I’m given. But if any food is involved I start at 20% on the subtotal, then round up or down to the nearest 50¢ or $1 depending on how long I stay at the establishment and how much the subtotal is.

For takeout, I’ll tip less since I’m spending much less time in the establishment; I might round the total up to the nearest $5 or $10 depending on how much I spend.

And for delivery, I have basically never ordered for delivery in my entire adult life, and don’t plan to, I’d rather just go and pick up whatever I order. I was a pizza delivery driver before UberEats and the like were common and quickly got a feel for that etiquette (people were usually pretty generous) and decided it was a luxury I could live without.

Compared to you I guess I’m a bit cheap but I’d still tip the same even if front-of-house people were making more money, unless they explicitly tell me not to tip them (which has happened before). I don’t think people should feel bullied into tipping, because I think the business should be paying them the living wage instead, but just like at any other job good performance should always be rewarded.

Sometimes this one place gives me $20 of food before closing when I only intended to spend $5 so the upsell kinda hurts

But that upsell is strictly self-inflicted. If it’s before closing, I can almost guarantee the staff are just hooking you up because a large amount of that food is just going to go to waste since most restaurants require things to get thrown away (e.g. if it’s a deli, some of the meats may have hit their shelf life limit).

I’d just tip what you can comfortably afford and what you feel isn’t insulting (e.g. tipping someone like $0.50 on a $20+ order). I always follow the 15-20% rule, and possibly higher in some circumstances. But I don’t know, I haven’t worked food in 20 years, so maybe the manners/expectations have changed nowadays. Also depends where you live.

How often does this happen? What is it costing your friends? Are they sneaking it to you? Are they the purveyor of the establishment?

In any case, if you were only going to spend $5, you don’t have to accept the full $20 worth of food/drink. You could say, “oh I was only planning on spending around $5 tonight, this is too much, but thanks.” Or if the somewhat direct approach feels awkward, max out your tip at what you were originally going to spend. If it’s not enough, they’ll stop giving you so much.

I would usually tip based on the total including free food. So if the total was $20 I would give 15-25% - probably 3 to 5 dollars. In the case of getting just a free drink, I usually tip the price of the drink, similar to what you mention.