There were probably some who wanted to try something targeted/infrastructural to avoid that, but there were also some advocates (including Jewish ones) who explicitly supported bombing the camps, including their occupants, because even if they died, it would be net-life-saving as future waves of trains would no longer have a place to go.

PBS's "Secrets of the Dead" series did an episode about this last year: https://www.pbs.org/wnet/secrets/bombing-auschwitz-wnrzgw/47...