Simply by virtue of your decision to enter the same industry, your co-workers and yourself have mutual interests. Once you get used to the idea of befriending someone outside your traditional peer group, you'll likely find their perspective refreshing. You may have similar tastes in music, movies, and literature. Work friends don't necessarily have to become social friends. If they make your workday enjoyable and offer humor, guidance, and interesting conversation, then you need not take it any further.
Boundaries are a good thing.
While no one is suggesting you cut traditional friendships short, it may be easier to keep borders between your work and non-work lives. That way, outside tensions won't creep in and you'll truly be able to leave work behind at the end of each long day. There are other options. If you're in the market for a new social scene and are disappointed by the lack of potential at work, there are other places to meet new people. Look into local sports clubs, volunteer opportunities, or outside classes.