A few that drive me up the wall is when I say thank you, I receive these responses:
"it's all good"
What happened to you're welcome?
A response meaning, essentially, "It's no trouble at all," is actually pretty common around the world. In Spanish, for example, you might say "de nada" which means essentially "it's nothing." They're not meaning to insult or annoy you, they're telling you they're happy to do a nice thing for you and that you're not putting them out at all.
Some people whom I knew, very long ago, adventurously went on holiday to what was then Czechoslovakia. They tried to master a few basic phrases in the local language, including “thank you very much”; which I gather is something like (anglicised), “motskrat dyekuyi”. Being fairly averagely-silly late-teenagers, they were tickled by this phrase, which they morphed into “muskrat thank-you”. From which they developed a joke by which every time one of the party did something thank-worthy for another, the “thanker” said “muskrat thank-you”; to which the “thankee” had to make a reply involving a North American fauna specimen, and a variation on a gracious response to “thank you” – both, different every time.
Such as – timber wolf you’re welcome
bison that’s quite OK
skunk my pleasure
bear not at all
cougar no problem
musk-ox the pleasure is mine
bald eagle no worries
opossum no trouble
beaver that’s fine
wolverine glad to help
roadrunner it’s good
caribou happy to be of service
coyote that’s all right
mountain lion not in the least
cardinal prosim (getting desperate – Czech for “please” – acceptable local
The party being all Brits with a less-than-encyclopedic knowledge of North American fauna, both repertoires were run out of before long; but I understand that it was fun while it lasted.