I often give the guy who rotates my tires and airs them up. I am having a new AC unit being replaced in my home. Do you normally tip these installers? Ed

No do you tip the clerk and the grocery store, the guy that changes your oil, your Doctor, Lawyer as well. Tipping has been blown way out of proportion. They are shaming you out of money with PC and doing very little for it in a lot of cases.

Sure, why not.

It's your money, you can give it away as freely/hoard it as you choose to.

I tried it as a teenager but i was always afraid the cows would fall on me.

My son worked residential HVAC over the summer basically as a gopher. He received one tip when he delivered a new AC unit late in the afternoon on a Friday so it could be installed that evening. He was happy to get the tip but it's not expected.

I'd just give them some Gatorade/bottled water

I went to a coffee shop in CO.

The coffee was overpriced and a tip was expected at time of order. The most surprising thing was that customers were forced to bus their own tables. The cashier and barrista (?) never came out from behind the counter.

Why they were deseerving of a 20% tip is beyond me.

Americans are known for being ridiculously big tippers in many developing world nations. The locals get quite a chuckle about it and one popular cartoon showed an American leaving a tip for nothing more than when a local passed wind.

No

These guys are making about 50 dollars an hour; they don't need your tips.

The Discount Tire by me has a spot where you can pull your car up, and one of the lackeys there will come over and air them up (or down) to whatever pressure you specify (at least what I've specified.. I don't know if they have rules regarding what's "too much"). It's free, and they always do it with a smile. I frequently tip the guy who takes care of it for me a buck or two, mainly because they have a good attitude.

I will occasionally tip non-professional service people if they do an exceptional job with the service and/or the personal element of the interaction (i.e. Very friendly, communicative, etc). Usually it's delivery men and similar people. If tradespeople are helping me at my home, I try to offer them food and drink instead.

Tipping is way overblown in the USA, but I'd be curious to better understand the basic wage structure in other first world countries where tipping is less. At least for food service, we even have a different minimum wage structure.

Tipping for food service employees is assumed and you are quite right their wage structure is low for this reason.

Tipping is not done at all in New Zealand. Thanking a person for a job well done is usually done with beer. Sometimes I've had people slip me a bit of cash for helping them out on the road when bringing a box in is not possible.

Sign me up where do I get this job.

Yep. Plus they are part time with zero benefits.