I had a ecommerce startup 5 years ago and we couldn't take credit cards, because payment gateways sucked, and the chain of effort around legally doing it was too much for a startup. So 40% of the work was just validating payment, and the other 40% was logistics, which left us very little room to grow.
I think it's satisfying to do B2B stuff so the B2C folk can just focus on being creative and doing what they're good at. I mean as FE I end up doing mostly B2C, but there's a lot of wiring under the hood, and we do things that the competitors have trouble with.
Even when I did e-commerce, it was very satisfying. We sold health ingredients. This stuff was easily accessible in urban places, but we got it into more rural areas. One notable testimonial was a woman whose husband cheated on her because she was fat, and the app helped her take control of that and start eating healthy. But the community ended up a little cult like (people were dieting to the point of passing out), and we realized we created a monster and sold the company.
I think the field doesn't really matter, as much as the company you're working in caring about the people they serve.