How do you know they have not taken action on them?

Sadly it is a case of buyer beware and you must look at the sellers feedback before buying anything.

These days new sellers have to wait 21 days to get access to their money when paid via paypal to help reduce scammers.

As long as you pay with paypal at least you have buyer protection because with bank dep or other payments unless a credit card is used you have no protection at all.