But you are not paying for a service, because funding OpenSSL is a classic free rider problem: the company would be better of not funding OpenSSL, even though all companies would be better off if they all funded OpenSSL.
By that logic, the tax accountant could argue that they should arrange a company's finances so they pay more tax, in order to pay for more "stability" by funding the government.
Does it matter about everyone else though? Your company values rock solid encrypted communication and it willing to pay a premium to ensure this it remains rock solid. The fact that everyone gets it is just a side effect of that.
It's not for the IT employee to effectively give away the companies money by buying something for more than they have to spend.
The decision to donate to a good cause is usually made by other people in the company.