Your choice.
Most here feel like giving their sources is inviting competition. Never much bothered me, but that seems to be the attitude here.
Or, more correctly, maybe it's "I had to work and/or pay for it, so you are going to have to, also."
Probably some of both.
But if you are going to he offering your goods or services you will have to pay to stay.
Not my rules, I wish it was free, but that's just how the thing works.
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