Photography

I know this post will get downvoted to oblivion but I'm genuinely curious. I hear lots of talk saying that heavy gear and lenses cause people neck pain and it hurts to carry all that 'weight' around. I'm currently hauling a Sony a7iii with the Samyang 24-70, the heaviest standard zoom lens for that mount, and the whole setup is around 1,6kg; I'm a concert photographer and am no stranger to having the camera around my neck or in my hands for up to 3 hours at a time. However I NEVER experienced any discomfort, matter of fact I enjoy the feeling of weight in my hands. So my question is, how come so many people complain about this problem and are seeking to cull every gram from their gear? Are people too weak to carry a mere kilo around their neck? I genuinely cannot understand