You're missing the boredom factor.
My mate got divorced about 5 years ago, got massively into rock climbing shortly afterwards. Would go on weekends away, every evening.
When he met his current partner he dropped it like a stone.
Men often end up with a lot of free time after a divorce. They still generally see the kids less, and often don't end up in a shitty little flat so that the kids don't have to move out of the family home.
Who wants to go to a carvery by themselves, or Ikea? And sitting in front of the TV every night alone with a chinese in your crappy flat is a surefire route to depression.
So some men throw themselves into work. Some find themselves a bunch of single buddies in the pub every night, and some find a solitary hobby, like rock climbing, or running, or hiking, or cycling, or surfing.
The ones who do the latter are likely to be the most well adjusted ones, so don't write them off too soon. Go on a few dates, if you find you're struggling to schedule them in around his hobby, then thats a sign he ain't giving it up any time soon. On the other hand, if he's happy to ignore the call of the wild in order to spend time with you, he's likely to seriously reduce the time he spends doing it going forwards.