I must admit to having been a bit snarky.
I believe that in much of American journalism these days, for headlines they routinely omit the word "and" and substitute a comma, probably to preserve space. It often makes for difficult to parse headlines though, something that I have encountered a number of times more recently on El Reg unfortunately. Headlines are supposed to be snappy, but it kinda defeats the point if you have to read it 2 or 3 times to figure out the grammar.
That might have made sense in a newspaper column, but most people are reading this on a large(ish) display with text reflow so not really an issue in this day and age.
Another humorous example was "Man, dog implicated in attack" or somesuch. When you read it quickly it feels more like "Man, dog, implicated in attack", which is probably a little harsh.