So in my work life, I am 'the man', by which I mean every morning I wake up, put on my corporate issued personality, and go forth and middle manage. In corporate speak, it's not that the bag is worth the extra $100. Most of them are probably sewn by the same Indonesian children who put out Kathy Gifford's fall line. What it is about is the signalling. Some will look at the bag and say 'that's an adventuresome guy who is ready to take on the world, and doesn't mind getting his white collar dirty in the field'. Some will look at it and go home and google it, and when they find out what you spent on it, they will decide whether to be jealous or concerned that you are making more than they are. Your underlings may look at it and decide whether you are professional and upwardly mobile, and then determine whether they should align themselves with you or not. Some will wonder where your velcro wallet is and think 'my god, I have kids older than this guy'. The bag dorks will give you a knowing nod that fills you with a warm glow of recognition and respect. And the front line mostly won't care.
So if you ask what separates the $40 bag from the $400 bag, the answer is usually a whole lot of signalling. I won't say that it is unimportant, because anything that affects your ability to provide for your family or be able to afford that extra brick of .22lr or fully fund your 401K is important. Signalling also goes on in every industry in one form or another. For my independent contractors, it tends to be all about who drives the biggest truck. As to how important it may be to the public at large, the truth is 'not very'.