it's ok to feel bad for people burning to death, regardless of the circumstances. it's your choice whether or not to give your sympathy to even the worst people. sympathy is hard to come by, especially on the internet.
you can paint two very different scenarios based only on a few facts, and that interpretation will determine how you feel about it. i don't know the details, nor do i care to. it's tragic to me, even if they brought it on themselves and deserved it in that sense. those two determinations/opinions are not mutually exclusive.
however, it is a bit odd to emphasize your lack of sympathy by starting a thread about it. i struggle between caring and feeling for others, or not feeling much at all. it's hard for me to hold onto the idea of life as sacred or precious in the face of what the world seems to be. where you stand on that question, on any given day, is the relevant thing here.