h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

A tip is expected for almost any service - if not just a common courtesy to help compensate someone who is paid little for their work except for tips. Taxis, restaurants, food delivery folks all should be tipped. Generosity is appreciated, stinginess or no tip for bad service is understood or grudgingly accepted - It might seem your waiter beleives in Karma - just make sure that if you go back again, return a favour or don't eat there.

In Monterrey, you can find a parking meter and pump some coins in - it could be a meter with a short time limit. If you do you might be reminded that you could have asked the patrolling meter cop to watch the meter with an appropriate "tip" to keep him motivated, just in case it runs past the maximum time and you promptly get a ticket.

If you take a cab in Mexico city, they have to use the taximeter by law. If the meter is "broken" you can get out and catch the next cab which will be waiting right behind. Otherwise, if you are adventurous, you know where you are going and your Spanish is good enough - you can negotiate a price. If you do, make sure you settle the price with tip included or calculate your negotiating price minus a tip. Otherwise it is common courtesy to tip the metered amount. In my experience if you are travelling all over the place in Mexico city, you should now where you are going - as the taxi driver may not, and may not have a map - It is not like catching a cab in London where they all have the "know". If you do find an organised cabbie who gets you where you want efficiently you should consider that. If he is not so organised, and you have to pull out your city road map - consider that he probably has a hard time making money driving you around for hours except on the extra income from tips, and the cab fare is very reasonable to begin with - maybe the road map (Guia Roji for example) would make a very nice tip.