Yes. I frequently do it, & it usually saves a little bit on taxes when they're booked all together, something about maximum taxes being allowed on 1 ticket, or something.
When I find a cheap fare, I'll frequently look for another cheap fare from that initial destinmtion, then return, then home...eg...
I found a cheap fare to TPA, then another cheap fare to SAT, so I flew PIT/TPA - 2 nites, TPA/SAT 2 nites, SAT/TPA 1 nite, then TPA/PIT & it came out $20 or $30 cheaper than if they were booked separately!
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