I just asked a close friend from Gran Canaria and he replied that no, it is not common, not even in the Canary Islands.
I say "even" because men local to the islands would colloquially address each other as muchacho ("boy"; sometimes pronounced like muyayo), but for a waiter to address an old(er) person as chico does not seem to be common.
Also, in my experience, that is unheard of in the rest of Spain. The usual way for a waiter to address an older customer would be señor / señora, caballero (for male customers), etc.