There's not really a single tag or app I know of to list all the places that do accept Steem unfortunately. There's the site Steem Locator for more physical places that take it, but it doesn't have many entries and don't know if it's up to date.
I did see an article on a prepaid card called Bitwala that accepted it, making it easier to spend at places. But it would definitely be nice to have a good up to date list of places taking steem directly.
Thanks for the hints!