Why would there (necessarily) be more money?
> People are also likely to start charging more because everything costs them more and people have more money to spend now
It seems like all of this would work equally well as an argument for a policy of depressing wages as a way to makes everyone better off. If you wouldn't support that, why the concern about guaranteed income? Or, what is the difference, in terms of effect on the money and labor supplies? How would lowering wages not be the inverse of this, and (under this line of reasoning) be good for us? Unless you believe we're at some sort of maxima for the ideal share of money flowing to the bottom of the economic pyramid, and that sending more that way will make collectively less well-off. It's also possible I'm just not following what you mean.
But people have to be willing to exchange things for money, so if you create tons of it, it becomes toilet paper. We already know this can break down due to direct, empirical observation. Just look up past examples of hyperinflation: https://en.wikipedia.org/wiki/Hyperinflation
And this is the sort of thing that worries me. All the past examples had to drop their own currency, which they could no longer be trusted with, and become dependent on a foreign power. All the past examples were governments that though the government's funds were simply unlimited and many were Socialist governments that wanted to tax from the rich and give to the poor.
That said, don't get me wrong. If I could actually believe that none of us had to work and robots would do everything, I'd love it. But having worked a crappy ass job, I know that some work can only get done out of necessity at present. I really hate that, and I don't wish it on anyone, but I don't know how to fix it either. I wish I could be convinced that some of the fine, caring people putting out these proposals had thought them through, but they've mostly helped me understand that they know less than I do, and I know almost nothing :/
[2] It's not just pay. You CANNOT pay me to do that job again. I'm sick of being cut by glass. I don't like dealing with horrific bloody injuries, though I'm incredibly conflicted there--I mean, I did volunteer for it and I don't regret doing it and helping people. And I'm glad to be able to do it and that I was able to help people and I'd even volunteer again... but it's a horrible thing to have to do and I don't wand more of it.
Basic income is just welfare on steroids. The effect should be something that depends on the scale of how much money and how many people have their 'stake' diluted by how much. The scale of this is bigger than before (everyone gets money) according to what's planned--I don't seriously think anyone will implement it as $5 for everybody and if they did, it shouldn't have any meaningful effect.
Due to more money being issued, there should be more inflation caused by it, as we can't all suddenly start producing more windows and whatnot just because we're paid more. People are also likely to start charging more because everything costs them more and people have more money to spend now.
Now, all that said, maybe it could work as a replacement for welfare. I'm not sure about that, but it doesn't seem terribly unreasonable. Maybe everyone has an ID card and they can charge $X a month for food/rent/clothing, especially with the theory that people who don't actually need it might not use it. As I said, the main issue is the scale. If you get to the "work is optional" state that everyone seems to want, that's where I worry about the effects. But, there's obviously a long continuum between it being 0% optional and 100% optional and I honestly don't know what things happen where.