Personally, I wouldn't pay for testing, but I can understand why people are doing it. Sometimes you need negative test result, for example before travelling to foreign country and there is no free way to get tested. So, people in such cases are forced to pay.
Also, I remember back in March in many countries there was lack of tests, so people had to be tested in private laboratories, in my country cost of test was €70 IIRC.
Personally, I wouldn't rush to get tested even if test is free. Even if I would feel little symptoms, in such case I just would stay at home.
in my country, in order to get on the train, we need a covid19 test...
It"s ridiculous and useless thing. You can get infected while you wait for test result and while travelling to the train...