The two are fundamentally different. Unless you can devise a way to do BYO expense platform, you're comparing B2B to B2C product development, marketing and sales.

Do you think the PMs at Concur just woke up one day and decided to be user hostile because they're asshats? Of course not. They did what the Sales team, and Gartner, told them they needed to give to CFOs so that they would buy it. And then CFOs bought it.

Until someone can quantify the benefit of "better UX" to CFOs, or provide that and all the CFO facing features they want, crappy expense platforms will continue to be the order of the day.