I pretty much live my life in the way I think best.
I actually DO tip Mike, the guy who gets my garbage, and Jim, my rural mail carrier, and Rob, the fellow who plows my driveway. It isn't often, but at Christmas, or on a birthday, or if the snow bank is plowed a second time at the end of my driveway, I remember them. I also make a pot of coffee for the road crew working on a ditching project in front of my house on the town road, or occasionally pick up the tab anonymously for a cop or firefighter in uniform at a restaurant. I try to find a manager or supervisor, too, when I can to make sure they know that Debbie, or Don or Maria took good care of me and represented the business (restaurant, hotel, carting company, whatever) well that day.
I do it because I like to, because it makes me feel good - not to supplement poor wages, or because I "have" to. I do it because it matters, even if just a little bit.
What I do is a reflection of who I am, nothing more or less, and it carries no weight of obligation for any other. Eighteen pages of interesting discussion, and I'm still giving Mike a McDonald's gift card for his birthday in March just 'cause I appreciate his weekly garbage runs and the occasional banter we share about pets and family and the weather.
Yep, I occasionally tip the garbage guy, personally. But neither of us "expects" it. Your mileage can (and should?) vary ...