Purpose of resistors across HT

[Chuck H]

I have a hypothesis that it may be better for the cap life, especially with gear that might not get used often, to allow them to retain some level of residual charge, rather than forcing a drain down to 0. As it may help to keep them 'formed'.

This makes sense. And it might partly explain why we sometimes see very old amps with original power supply caps still functional. Sometimes I think those those old Mallory tan/orange cardboard caps must have been made on another planet.