My Chem Show in May.

I'm looking for tickets to the My Chem show in May.  I have found some at some decent prices, but I'm reluctant to buy 'em at this point.  There are different tickets for sale for General Admission and Floor.

I know 9:30 is a GA venue, which makes me question why there are different types of tickets being sold for this show; I feel the need to question their validity. 

Maybe it's a dumb question, but I don't do shows.

So any advice would be cool.
Thanks.
Purchasing tickets anywhere other than Ticketfly or the 9:30 Club Box Office is not advised.  Additionally, all tickets for that show are indeed General Admission.