YES, they definitely are, even in fact, when they shouldn't.
for example, on 12/26 I had to change a rez to avoid JFK during the blizzard, and AA said they would refund to my credit card after I had to rebook on AA.com. However, 3 weeks later, a paper voucher for $1725 showed up in the snail mail at home!!! Now AA has my money, and I can only use the voucher by going to SFO to apply it to another ticket. (I rarely have time to send it in by mail to apply it)