I wouldn't call this abuse - it's a marketing tactic, and it's rarely hard coded, more likely selected by default - at least that was my experience.
Just to add some numbers for perspective. In 2018 there was 763M PLN (~$200M USD) to split among 9000 approved organizations. The largest one got 166M with another 100 orgs getting 1M+.
It doesn't work exactly this way in France, but any donation to a registered non-profit gets you a 66% rebate of that amount to your income taxe (within a 20% limit of your taxable income).
Yeah, it's the same in the result, but the barrier of entry is significantly lower (easier to fill 1 field in tax form once a year than to make a payment and then get a refund).
We don't get a refund (perhaps I misused a word in my last comment): when filling my tax, there's a box for amount donated, which is then used when calculating the amount of money I'll have to pay as taxes.
But yeah, the barrier is higher, but I think the choice of organizations is wider in our case, like the organization to which I gave money the last two years wouldn't be on the list for example.
It's a nice idea, even if some organizations abuse it (they give out free tax-filling software that has their organization hardcoded).