Snow foam is wax/sealant friendly and yes it would help. All that snow foam does is help break down some of the surface grime before touching the paint with ya mitt. My method is:-
Wheel cleaner
Jet wash whole car
Apply snow foam - make sure and let it dwell long enough. I usually use this time to run my wash buckets.
Jet wash foam off
Wash - two bucket method
Rinse
Dry
Etc
Etc
Don't know if this helps? Also remember to store ya snow foam indoors (somewhere warm) otherwise it'll separate in the cold weather, once warm again it'll go back to its proper state.