Members of the union that represents the folks behind the wheels of corporate shuttles stood and sat in front of those buses in the Castro district, demanding a secure pension for high-tech shuttle drivers. About 40 Teamsters blocked tech buses in a surprise protest. The drivers were from WeDriveU and Loop/Hallcon and transport employees for high-tech companies including Apple, Tesla, Amazon, Twitter, LinkedIn, Salesforce, Electronic Arts, Lam and Facebook.