Jeans are a terrible terrible choice for anything other than a low level activity.
Through in changeable weather conditions and they're even worse.
Anyone that says otherwise has absolutely no experience in mid to high level activity...
Does logging count as a high level activity? I mean real logging (cutting and haulng trailer truck loads of sawlogs from the hills and swamps to the timber mill; NOT just cutting firewood.
Or what about hiking up and down the Rockies and the Humbolt Moutains (up to 12,000 ft.) in both Summer and Winter?
Or the Mohave Desert?
Herding, roping (or sometimes bulldogging), and branding, cattle for 12+ hours a day?
Loading 85 pound hay bales for 12+ hours a day?
What about fighting brushfires in the deep Summer?
Shall I go on?
But perhaps as HillBill said, you simply don't get good jeans there; there's a vast diference between fashion jeans and real work jeans. The plain truth is I don't wear anything special for bushcrafting or outdoor activities (other than the occassional camo, which might well be camo-ed jeans) I just wear the same clothing I wear all the time (work, play, or casual dress) That is, apart from the time I was required to wear a uniform; and those were a jeanlike material (except for the corrections BDUs which were a very unsuitable, thin, soft cotton)