The Swiss people living here...
The Swiss people living here in Lucerne are really friendly and VERY polite; so please be sure to greet them with a warm 'Hello', 'Goodbye', 'Please' and 'Thank you' in either German, French, Italian or English (yes, they are multi-lingual!) whilst entering and leaving the shop premises. We certainly don't want these lovely Swiss folks to think that we tourists are a barbaric bunch, yes?
For the absolutely curious amongst us, 70% of Swiss people speak German as their first language; 18% French, 11% Italian and 1% Romansch. English is understood and spoken (to a certain degree) in most places where you'd find tourists. However, in smaller towns or shops off the beaten path, English is hardly spoken. So, in order to BLEND in with the Swiss, speak GERMAN!!! I'm sure your attempt to speak broken German will be greatly appreciated by them. I tried and it did work... even though I have NO CLUE what I was talking or speaking about. Duh!!
Oh, and in case you haven't already figured out, ALL THINGS Swiss are SUPER-CLEAN (not even a speck of dirt anywhere!), SUPER-EFFICIENT, SUPER-ORDERLY and yes, MEGA-EXPENSIVE!! :-) Have a great trip!