The last couple days, I wasted over a 100 EUROS = 130 USD on Steam and not on GOG, because of PaySafeCard.
And the Holiday promos aren't over yet.
Why on Steam & not here? Not because I will ever PLAY anything from either site - but because I live in Europe ( work in IT security = paranoid = don't like my credit card to be cleaned out online).
I have a PayPal account (the irony - I know), but use it by uploading limited resources via my bank (bare with me!) PayPal has my bank account number - but only I can send THEM money. THEY cannot TAKE any!
Oddly, the time it takes to transfer money takes several days. (I think, PayPal is using J.P. Morgan in Frankfurt as a clearing house).
And now - between Holidays - I have lot's of EURO coins in my home. There's a ATM like Prepaid Card Machine 100 yards from my home. I pass there, almost every day, drop some coins in the machine (machine=coins=videogames) get a receipt with a PIN number and go back home, where I can upload the amount I threw in that machine earlier to my STEAM WALLET.
Impulse buy. Purchase instantly. No hassle. No need for ID, Age verification, no endless piles of user data, you have to figure out how to 'protect' according to whatever country your customers on GOG live in. It's like a credit/debit card purchase, but only in reverse.
That's why I spent 130 bucks on STEAM the last days ... and counting, GOG-Duders.