Originally, fajitas was a cheap piece of meat that could be tenderized in several ways (papaya enzyme, lime juice (preferred), orange / lemon juice). See
https://en.wikipedia.org/wiki/Fajita. I used to buy it at HEB, already tenderized, and just open the pack and barbecue it.
In Texas, fajitas are a staple meat. Breakfast? Fajitas + eggs + salsa, served in a tortilla (translation: taco). For lunch and dinner, fajitas with bell peppers and onions, sauteed. (also: taco). Very, very tasty, and healthy from my POV.
This is very good and quick food. The cost is that the fajitas must be marinated for a long time before cooking (24 hours), to be tender. The benefit is a meal that people look forward to. Nothing in Swiss street food comes close (döner doesn't cut it, sorry).
Clearly, I'm trying to promote my personal comfort food here in CH. Not a sin, but I would like very much to gather some enthusiasm from people here.
It would be so nice to go to a grab'n'go place, not pay a fortune, and get a really nice meal. Maybe other folks feel the same.
This is a significant difference living in CH, and I want to try to establish inexpensive street food, NOT döner, but something everyone will like. Shout out if you agree. We might be able to make it happen!