a lot of it is just cultural approach. math people tend to like to rigorously define everything they're doing, and work from there. physics is more like "what can we make up and fudge and twist and bend and then get the right answer." there's a lot of people who aren't as comfortable working in that less-defined context.

some of this is maybe inherent to the aim of physics, some of it is just physics machismo culture, and could be better, imo.

(i was a physics and math major at oregon.)