I was shopping in a massive store that we have here in the United States where they like to move everyone really fast out the check out line. They pack you up and get you out super fast but then a lot of the times things are squished and ruined. I like to bring my own freezer bags and pack the things myself.
Today a manager came by and wasn't pleased with where I had moved my cart or that I was going to pack it myself so he started swearing about me in Mexican Spanish with the cashier, in a low voice, but I was right there so could hear. It was really fun! I know though that in Mexican Spanish swearing is just part of how everyday people like often to talk so I honestly wasn't offended and it really was just too much fun to be able to listen in.
When I left I thanked them in Spanish in a way where they knew I understood and they both lowered their heads and looked a little frightened. I don't LOOK like I should understand Spanish! I look like the only foreign language I would speak would be a Slavic language. :D Was I going to report them to the management? Hopefully my smile reassured them. I doubt if they will ever assume a customer can't understand their "palabrotas" (swearing) again though. ;)
Also, never assume that someone DOES speak your language, especially in areas where it is not an official language. Many English speakers tend to do this in foreign countries where people may not speak English well.
I used to work in a supermarket with a japanese guy who was born and raised in south africa. a couple of south africans came thru the till one day and started complaining about the recent immigration of asians to vancouver lately in afrikaans right in front of him . Lets just say they were suitably shocked when he added his opinion into the discussion...
Well, I was at work and I was just talking to one of the cashier girls when two women arrived. They were just looking at the menu and after a while one of them started looking at me. At first it made me feel uncomfortable but I ignored until I heard them say things like "ugly bit**" and other stuff. I almost laughed because one of them actually said "they look so stupid, no clue what we're saying" (not exactly, that was three years ago) so I decided to greet them and ask how I could seve them. It was so fun to watch their horror striken faces xD! They didn't say anything else, just kind of stuttered and turned to leave. My friend was clueless to what happened though.