So “earning a profit” no matter from whom or what, especially in the name of some cause that may be against your beliefs, is not serving Mammon? Okay then; that legitimizes the Mafia.
I asked the OP if the Apostles did it this way. I got no answer. Proverbs 25:22 and Romans 12:20 do not involve compromise of one’s beliefs for the sake of money; rather, it seems no profit motive is involved, and I do not see how what is suggested here is an act of kindness that will promote religious freedom rather than undermine it. Think Acts 5:29 instead.
If all the money earned is donated away, where's is the profit?
especially in the name of some cause that may be against your beliefs
The money earned would not be in the name of some cause that may be against your belief
but rather in the name of some cause that conforms to your belief.
Because you are upfront about your catering,
in effect the cause that may be against your belief
is donating money to the cause that conforms to your belief.