People are going to spend money in ways you don't approve of. Period, it is part of life. I truly believe that we, as a society, shouldn't let that take away something that can help a bunch of people.
Free public transport is the tragedy of the commons in inverse. Free roads mean public transport can barely compete against cars. The convenience of a car simply cannot be compared to a bus but the real question is, why is it so cheap to drive yourself? Shouldn't it be far more expensive? If people abuse free public transport that is actually a good thing.
>For example, what would be stopping land lords from hiking rent prices?
Nothing, nobody guarantees that you get to live in the most expensive locations on earth. Please move to a place where your UBI is enough instead of trying to drag down the most productive members of society (indicated by their ability to pay high rents) and by productive I just mean economically (nobody gets to tell how to live your life), which means they are the source of the UBI income in the first place so it is in your best interest to make sure they succeed.
>And what would happen to addicts who use their UBI to buy drugs instead of food and shelter?
They will rob less stores and houses to fund their drugs.
Yearly taxes on my car are higher than a yearly public transport pass, yet I still have a car. Public transport could be free, they could even pay me for each trip and I would still have a car, simply because my car takes me to places/times that public transport doesn't.
I'm all for public transport, and I use it regularly, but it is not a complete replacement for a car. In fact if you make it free people might even use the savings to buy a bigger car.
Exactly the same things that are stopping/not stopping them now?
UBI won't magically make everybody non-poor, no matter how you tweak the numbers. But it creates a gentle slope where everything means-tested creates harsh cut-offs full of bad incentives. It prevents many things (even if not all things) that make up the trap-like nature of poverty.
In this case (UBI) literally everybody knows 100% that you have more money than before.
This argument doesn't seem specific to UBI, but could be raised towards giving anybody money for anything.
Maybe some landlords would initially raise prices, but presumably competition or alternative housing options would push the prices down again.