Hi ivanbranco,
thank you for your comment. I removed the tag for your satisfaction.
Indead it seemed like i was the only one using this tag.
Both of your proposals dont seem right because they arent relied to the maximum customers. They key capcity could describe the maximum capacity for dresses, measurement cabins, parking lots, etc.. And the word capacity kind of describes a physical limitation. The maximum customers this shop allows is no physical limitation but absolut artificial. All other examples on the wiki page describe physical limitations (Link: osm.wiki/Key:capacity).
Since I removed this tag only because of your comment, can you please explain why somebody should not introduce new tags? When the time is right and all corner cases are described we can clean it up anyway. In future I expect the OpenStreetMap workforce much bigger then today, because since its beginning the OpenStreetMap userbase and changes growed continously.
Thanks and kind regards,
redd