I guess many of us here are accustomed to the use of email aliases or temporary email addresses.
One thing that’s not uncommon in the US is to do the same with phone numbers: If a service requires you to give them your phone number, you don’t use your real phone number but a temporary forwarding service.
To my knowledge there isn’t something similar in Switzerland, is there?
Would love that service.
Not sure if what I have in mind is what you call “burner phone” but I would buy a Lycamobile SIM card and put it in an old phone. Done!
With Lycamobile you don’t need a plan to receive SMS and (EDIT: almost) everyone has an old phone doing nothing somewhere. 
Huh, what? We don‘t.
Burner phones are kind-of illegal here. You need to identify yourself to own a phone number.
You could use a prepaid SIM and set up a redirect to your actual phone number. But unless you get a new prepaid SIM every couple weeks, you end up with the same problem of unwanted calls and spam.
But there are plenty of online, prepaid burner number services.
What kind of services are you using, that you need a burner phone? 
I did a lot of questonable stuff, but a burner number was never needed.
They give you only US phone numbers, which are not accepted by local service providers.
Are there services that give you Swiss numbers?
I believe so. Hushed has Swiss numbers AFAIK. There is another one called Blacktel.io which apparently does as well. There’s one called online-sms.org that looks like more of an open-source thing that is just for receiving SMSs.
I guess a lot depends on what you would use it for. I definitely wouldn’t recommend using these kinds of services for sensitive information like bank 2FA.
I’ve learned to spend few rappens on a throw away SIM just to register any social network communicator. These are the source of number leaks and spam-calls. My new regular number which I’ve never registered on any social thing, stays spam free.
Something to add: It’s trivial to trace the identity of a burner SIM if you’re re-using one of your old phones. Get a used one off ebay/ricardo, or better yet, a flea market for cash.
Is this Walter White?