As long as they are not "eingedeutscht". That's a matter of language distance & time.
Niederrhein (Lower or Nether Rhine). We pronounce eg. "warten" like "wachten". Another regional feature is the missing sch-sound, most of us can only pronounce it like 'ch' in "ich".
BTW, 'ch' as 'k' is not restricted to loanwords. Take the examples "höchstens" or "nächstes Mal".
Loanwords are always from foreign languages, else they are not called loanwords, for what I know.
Hmm, you really have an issue with Bavaria, it seems. Don't be too negative! They are human, too.

BTW, don't forget that there is more than one dialect in Bavaria.
Pretty much every dialect in Germany could be regarded as a separate language, for being unintelligible with some other German dialects. If I would speak Jläbecker Platt (the dialect of my hometown) to you, you probably wouldn't understand very much either. Luckily for you, I myself cannot really speak it (& even have problems understanding parts of it).