Try rent beer tap for birthday party, he wants to charge per person but he doesn't even supply the beer?

We tried to order a beer tap for my birthday party

So we found a Portuguese supplier that rents them out

One problem is he only rents out the beer tap without beer, but okay we could get the beer somewhere else

We asked the price, and he asked us: “how many people will drink beer?”

I have no idea why this matters, normally you price a beer tap per liter, but since he doesn’t supply the beer this doesn’t make any sense

We responded with 30 people, and then in true Portuguese time: “I will send you a quote somewhere next week”

Of course the party is next week :D