I have actually used Mele Kalikimaka as an example of phonotactics when I taught Intro Linguistics. More examples I’ve used are English loanwords in Japanese, such as ice cream becoming something like aisukurimu, and Russian/Greek loanwords in English, such as /ks-/ and /ps-/ becoming kəs- or s-, as in Ksenia or psychology.
The other interesting thing about the pronunciation of “Christmas” is that its English pronunciation also shows adaptation of borrowed words from one language into another: in this case, Greek “ch” (chi or X) which is an aspirated /k/, not an alveopalatal fricative /tʃ/ which is what we most commonly use “ch” for in English.