I used to argue with my Japanese in-laws about slurping, now I do it on purpose
When I first moved to Osaka 6 years ago, I'd quietly eat my ramen and get side-eye from my wife's dad because silence at the table apparently reads as "this food is bad." Now I slurp loud enough that my mother-in-law nods approval, and I've learned it's not rude at all there, just the opposite. Anyone else pick up a habit abroad that would get you judged hard back home?
Did you ever get the silent treatment from your own family when you went back home and started slurping at their dinner table? My mom would probably ask if I was raised by wolves if I pulled that at her house. At least your in-laws are happy now, that's what counts.