> but why would someone toil to create a new algorithm to solve a problem if someone else is just going to steal it in hours?

The same reason I have open sourced every line of code I have written in the last several years, even new inventions. Because it is good for society, and good for my reputation to show what I am capable of which has been very good for my career.

Better to be the one to open source it before someone else does.

The only business model left is convenience tax. Save people time and they give you money.