I had trouble parsing this at first, so I'll share the breakdown:
"Merhaba demek" - To say hello / Saying hello
"Merhaba demek bile" - Even saying hello
"Merhaba demek bile bir hizmet" - Even saying hello is a service
Perhaps not--it's very similar to an Arabic saying, based on the teachings of a very wise man, "Even a smile is charity." It comes from a context where the concept of "charity" isn't limited to sending a donation, but includes removing broken glass from the public path, offering an arm to a blind person, giving directions to someone lost, or passing the kleenex box to dry fresh tears as well!
what does "even/bile" refers to? does it refer to "demek" ? or to "hizmet" ??