When I was in college, I once walked down a sidewalk that had been taken over by geese. Twenty or thirty big geese, sat down on the ground, who didn't even bother to get up on their feet I as I passed by. I wondered how they knew I wouldn't kick them, as I easly could have, and I concluded they had figured out that polite humans would just walk around them. Which I did.
I've seen the similar behavior from the ducks and geese in my neighborhood. Not as extreme, but sometimes I'm out for a walk, and they'll keep a wary eye on me, but will be content with the situation at 6-10 feet away, and won't actually take off unless I try to chase them. I don't think it's so much that they're "cutting it close" as that they're justifiably confident that humans are too slow to catch them at that distance and generally don't even try. But on the other hand, different groups of them seem to have different distances they're comfortable with. It's not like they've all solved the same optimization problem to three decimal places - some are confident and some are wary.
Of course, there are lots of stories of animals who got overly familiar with humans right up until the humans surprised them. As a funny example, I remember one time a cat that had grown up around my not-very-athletic family escaped the house and had to be brought back inside. At one point, it made a break for it along the long side of the house and was visibly shocked when my runner of a fiance ran it down and cut it off. This wasn't its first time running from us, but it had never run from him before, and it clearly didn't think humans could be that fast.
I don't think animals optimize as hard for benefit in everything as biology might lead you to believe. They build experience. They make mistakes. They're very cautious in new situations, but they can also be confident to the point of cocky if they think they know what you can't do. There's lots and lots of videos of cocky animals guessing wrong. It makes sense to me that maybe every individual animal isn't prudently optimizing hard for its own survival so much as that the group of them, with different temperaments, try different things and sometimes it works out and sometimes it doesn't and maybe there's a balance between weeding out dumb ideas and retaining the capacity to try things.
I think the idea that animals are always optimizing for survival and that everything must be for some benefit is misleading anyway. I mean, in an ultimate sense, you could say the same thing about humans, that they must always be optimizing for survival and reproduction, and whether or not that's true, it's definitely not true in a simple and obvious way on the level of day-to-day activities. We do a lot of dangerous and dumb and non-productive stuff. I don't think animals are different.
In fact, it makes sense to me to leave some reserve capacity. If surviving in good times takes all your time and energy, what are you going to do in hard times? Therefore animals typically have a lot of time for goofing off, and that certainly seems to me like what they're doing most of the time. They would similarly have room for trying stupid things and taking unnecessary risks.
A favorite video on the topic: https://youtu.be/UezzQSUwIgo