Nope, in my view gambling is a style of life rather than a hobby. True and abstracted gamblers will bet on everything even on tomorrow's whether and it doesn't matter with whom and where. They are gambling in the sake of process which is part of their psychologic life. I'm not in their class. For me personally gambling is a kinf of "hash-time" session when spending my leisure time.
Gambling can be considered anything, depending on how we view it. You can consider it as "life style" or "style of life" for yourself, but you can't generalize it. Not sure what you mean by "true gamblers" or "abstracted gamblers", but it isn't likely as a lifestyle if a gambler bets on everything and do it carelessly. IMO, it is just the way of wasting money with gambling if a gambler does it in that way. I think you need another example if you want to describe it as a "life style".

I'm also a bit similar as you. I just bet when I've free time (spare time). I'm not a typical gambler who push all my funds in a single day. I've an allocation for gambling daily, weekly, or even monthly. I'm not a part of those gamblers who can spend all my funds because of chasing the wins or trying to recover losses. When I have a bad day and get some losses, I'll stop it earlier in that day and return again tomorrow.
I would like to note that I often also come across a stereotypical perception by other people of the fact that I love casinos, betting and poker. They immediately start looking at me as if I could go and lose my entire salary in one go. But it's not like that!
And I strictly observe money management, I am proud that I have never been to tilt. I didn't break my computer mouse on the table when the opponent at the poker table got the best cards. And the like.
But "gambler" is like a label for a bad person, that's what others think.
Indeed, gambling could be bad for some, but it is obvious that it is not bad for all. Some people may love doing it, which is why I would say that, yes, gambling can be taken as a hobby as asked in the title of this thread. What you love doing and trying as much as possible to find time to do regardless of the money you use to access it is part of your happiness, so it could be your hobby. And if anyone can keep it reasonable financially and psychologically, then I call it a good hobby. This is especially true if you've built some kind of mindset towards it in which you can get refreshed after work or cool your head no matter what you are facing initially.
So, it is all about how we view it or engage in it, gambling is not so bad. Nonetheless, for those who are trying to gamble for fun or trying to make money with it under the right management, you have to ensure that you have a viable plan and budget that will speak well of proper management towards it. Anything outside this is going to ruin the party for the person sooner or later.