More often than not, I'm soloing and I don't even have the option to boot them. Even if I quit my own game in disgust they will receive Xp and a reward while I will not. And, as I said in my first post it's not always possible to kick these people immediately, maybe you're busy fighting or maybe you don't know enough people in the Pug to get organized about voting.
When I have a game going with people just from my friends list and we can stop to organize ourselves to remove them, it's fine. But it's a system that encourages these dudes to just keep doing it. Booting them once only removes them from that particular game session and they'll be able to come back for a free ride next time you're playing in a public game.
If you're just soloing more often than not, common sense begs the question of why you didn't set the room to 'Private'?
I can't speak for PC players, but organizing a vote-kick on the PS4 is a really easy 3 step system:
1. Tell the rest of the team, "Hey, xxx is AFK, we should probably kick him."
2. Rest of team votes to kick the leech.
3. Profit.
I mean, I can only assume PC has similar functions in this regard? While there are a lot of things that I feel could use improvement in DAMP, the ease-of-use of the Kick system is not one of them. ...unless they added a HUD icon over the players name that showed any kick vote skulls, maybe? To show the rest of the team that someone had voted to kick that person? ...nah, it's fine as is.