Being said that Adobe Muse will continue to be supported for OS compatibility until May next year.
You can further continue creating sites in Muse until its code is compatible with latest web standards.
Therefore widgets are still being sold by the third party merchants.
It's similar to Adobe not stating the EOL condition on the Muse Product Page or during Purchase Checkout.
As discussed here:
It appears any money left to be made is in progress even though the EOL is in place. I feel bad for the unwitting New users, who may have no idea regarding that fact. It really is a bit of veiled deception by Adobe and the 3rd party developers whom don't directly advise new purchasers or uninformed users of the EOL pre-purchase.
In my opinion.