It actually fits the definition fine.
That's what I get when I google for a definition of golf. Just because it's not by the rules you chose to follow doesn't make it another sport, it just makes it golf by a slightly different set of rules. What you are saying would mean, for example, that untill 1952 (USGA started to jointly issue rules with the R&A) people in the US didn't play golf, but a "game that sort of looks like golf".
And of course, Google is the standard by which we define the many different aspects of the sport.
If you're interested however, here's how the USGA defines "golf":
The Game of Golf consists of playing a ball with a club from the teeing ground into the hole by a stroke or successive stroke in accordance with the Rules.
Please note the "in accordance with the rules" thang......
In no game of pick-up basketball in this country is every rule of basketball adhered to. (The "3-seconds in the key" rule is the first to come to mind.)
Are all those people playing basketball, or are they playing a game that sort of looks like basketball but fails to meet the definition?
(And just to be clear, I play by the rules. I just think people who don't are still playing golf.)
That's the part that would possibly annoy me a bit. I dislike it when my buddies or co-workers do that, knowing they don't play by the rules.
Me too, and I know a lot of people that do that.