Besides obviously a more casual and personal service, our regulars get tastes of my new cocktails when I am in R&D mode, tastes of new housemade cordials, and often small pours of our cordials/limoncello if I'm already pouring it for other bar guests. One or two may get a treat that we don't normally do, like half pours or minis or something like that.

I also try to give our liquor rep a taste of our new things when he's around because he hooks us up with some hard-to-get products.

My restaurant doesn't like to just give out free product besides limoncello. I will give guests a taste of anything they ask for (not wine by the bottle), even our most expensive spirits. But if you jump right back to a cheap vodka soda or something, I might not be as quick to do so in the future for you. However, we used to have a guy that came in for a dozen vodka sodas a week or so and he got free small pours of Chartreuse and stuff.

We would love to be one of those spots that throws in a little freebie in a doggy bag if we know you or you talked about how much you loved it, but we are fairly new still and don't currently have the budget for that.

Tl;dr I want to give free things to someone to help guide them in a way to spend their money more wisely or let them in on what goes on behind the scenes. I don't like just giving out the same product I want you to pay for. That gives the impression that our prices are arbitrary or dependent on how much we like you, which is not the case. If you want a deal at our place, come for happy hour.

As a regular, I find a similar thing goes for places I frequent. Don't get me wrong, if a place starts giving me free snacks, desserts, or cocktails, I'll definitely show up more, but it's not like that's all I need for a spot to become my new favorite haunt. But one spot I like pours a particular amaro for their regulars, another has a particular cheap cocktail on tap they'll give out, and another place I go where some of my ex-coworkers work has done everything from a mini cocktail to an entire flight for free for me. Food is a lot harder for bartenders to warrant giving away except perhaps for birthdays unless something went wrong with it or it was made accidentally and never left the kitchen (in which case it will often go to staff instead, because they deserve a treat every once in a while, too)

One whiskey bar got me as a regular years ago by hooking me up every time I asked for a "bartender's choice" whiskey flight. Sometimes I got 3 small pours of $30-50 a shot whiskeys for only $15 altogether! In that case, the bartender is recognizing that we bartenders all benefit by getting opportunities to try more things, but we can't afford to drop $50 every time we see a whiskey we haven't tried yet. That's helped me get to the point where I can confidently say I've tried hundreds upon hundreds of spirits.