I think inquiring about other seat locations is fine.

To be honest, I think it more has to do with the person behind the window than it does any sort of etiquette. Some people are friendly and willing to chat with you, and some people aren't and just want to complete a transaction quickly and move on. (I honestly would've just assumed everyone was willing to chat, but when I was picking up a ticket for a lottery I won for Book of Mormon, I had asked about the seat location and the guy didn't respond, he just asked for my ID, gave me the ticket, and didn't even say anything else. I'd actually call him rude, but it wasn't an extended conversation where he said anything bad, he just didn't intend to speak excessively.)

I hope that doesn't discourage you from asking. Do ask, especially if the person seems friendly.