I also use the fob key for this reason as well.
I had a separate non-fob, non-stove key cut that I use. I never remove the stove/knob key.
For some reason, the lock on my gas tank is getting harder and harder to use/turn/insert/remove. I think it is starting to bend my "extra" key.
Are you aware of the modification so that you can close it without the key?
I push down on the gas cap before I turn the key. No issues with that or removing the ignition key to use for fueling up.