"Data from surface survival studies indicate that a 99% reduction in infectious SARS-CoV-2 and other coronaviruses can be expected under typical indoor environmental conditions within 3 days (72 hours) on common non-porous surfaces like stainless steel, plastic, and glass."
These are typical surfaces found on public transport, shopping malls, food courts. Three days allows for a lot of traffic to pass through and potentially come into contact with the infected surface. Of course, if the infection is coming from someone who is at that location on a daily basis (works there, takes the same bus/train each day) then the 3 days stretches out because surfaces are getting re-infected while the person is infected. Given that in densely populated areas such locations can get hundreds to thousands of people passing through each day, 1 in 10K may still translate to 1 infection every few days for a given "location". Each of those people would likely infect whoever they cohabitate with. So, while surface transmission is very low, it's not nothing, and can translate to real numbers in short order.
You may read the above and say "so what?". I should point out that I'm based in Australia, and the way we've handled the COVID situation and the numbers we've had and are having, means we are generally pretty highly sensitised to avoiding the kind of shitshow happening in most of the rest of the world. The numbers you are seeing in your countries are horrific to most of us.