I think a lot of it is down to people overinflating the importance of their work, or the qualifications of their team. You could have a legitimately talented team and have delivered successful projects for big-name companies, but I'd be willing to bet that there are half a dozen other companies within the same city with similar size clients, a similarly-skilled team, and equivalent work.
It's all marketing. A company might sell the fact that you're doing large-scale work for global clients, when in reality you're building shitty CRUD apps for big-name companies that have farmed out the work because it's short-term work for a single department.
The panel interview is always a weird one. I've known a few places do it, and it's usually because the company is flat enough that certain individuals want to assert control over certain groups of people. My old place did panel interviews, with leads from design, tech, and PM's sitting in to ensure they have influence on that team.