I was just wonderingIt seems this happens when Spotlight indexes the same thing. My theory so far is that those results were indexedapps before the changesetting to hide extensions was in settings being doneeffect. I'm thinking if I ask for a new indexing it might work You should try reindexing applications to resolve this issue.
UPDATE: YES - That was exactly it. I followed instructions and wentGo to Spotlight preferences in the Privacy tab. I added in Spotlight preferences and add the Applications directory to the list of removed contentexcluded locations. The Applications disappearedThis should remove all applications from the Spotlight resultsindex. Then I just removed Applicationsremove it again from the exceptions list. It was instantly re-indexed and allexcluded locations so Spotlight will reindex applications with the results didn't havecorrect settings. After reindexing the ".app" extension anymoreshould be removed from all results.