AENA is the organisation that manages Spanish airports. They operate a lounge in each MAD terminal, separate from the IB lounges.
You cannot pay to enter the IB lounges (which do have wines, of course), you can only get in with status or a business class ticket.
You can pay about 25 € for a pass to get in the AENA lounges (which are also associated with Priority Pass).
What people are saying is that, if you only want lounge access, it is cheaper to buy the pass for the AENA lounge than to buy the upgrade to get in the (nicer) IB lounge.
Personally, rather than pay for the lounge I would spend my money to eat something in the terminal, and then find a quiet bench to wait.