Studies on the accessibility needs of high-tech firms often draw on agglomeration economies and creative class assumptions that emphasizes how transit and walkability encourage clustering, knowledge exchange and innovation. As a result, some argue that knowledge-led economic development aligns with sustainability planning, especially as high-tech industries become increasingly tied to smart city agendas. However, due to the new logistic revolution, global e-economy, rise of online workers and urban land values, it is likely that some tech industries prefer strong highway systems, potentially leading to higher GHG emissions. As such, the relationship between the knowledge economy and sustainability outcomes remains unclear. This study addresses these gaps by quantifying the geography of high-tech zones in North Texas and Northern California, measuring their specializations, and exploring their differences in terms of transportation infrastructures. Our results only partially support research suggesting high-tech industries prefer dense, walkable, transit-accessible places. For instance, we found large numbers of high-tech firms (e.g. IT and aerospace) are still attracted to peripheral, auto-centric spaces, which is at odds with sustainable transportation policies. Hence, policymakers may need to revisit their growth strategies to not only succeed in growing their knowledge economy, but also secure sustainability goals.