So, you can pay through steam. However, SE considers steam a separate platform: If you buy on steam, you're forever tied to it. If you buy somewhere else, you can never use steam. (Don't ask me why XD)

Paypal's payment methods aren't a result of anything SE did, to my knowledge. In the US, they require you to link a bank account (You can pay with a CC, but only after linking). Paypal doesn't exactly have a great reputation, however.

Anyways, do you have a way that you can get a preloaded CC? That might be the easiest work around. In any case, good luck!