I don't make beats to sell them.

If you do that, yes you are making money, but selling beats to random people isn't the best way to get your music out.

I make a beat so other rappers that I think are dope, can hear it and see if they want spit over it.

I collaborate for free with any rapper if I think they are dope.

It's just a matter of preference, if you want to make money short term, or think long-term and see what rappers you think you might be able to go far with, then you make back your money.