Is this super tacky? Baby shower advice... Kind of long

Erbear
So... We live in Denver and we have an old amusement park that's a relic, it's like stepping back in time and I love it there. It's also super cheap, $20 on the weekends for unlimited rides, and I think a hotdog or something. ( we're going to provide food and drinks for everyone) Anyway, I REALLY want To have our Baby shower there. I know I won't be able to ride any rides, but like I said I just like being there. They have a kiddie area, picnic area, and we have A LOT of people to invite. My family is huge and all local, I have about 25 ppl from my work, plus a few friends from my husbands office and our group of friends. So a big venue makes sense. 
Here's where I'm struggling, I can pay for everyone's admission to the park, no rides for $3/person and they can buy individual rides or unlimited. But the park recommends I buy all the unlimited tickets ahead of time and ask ppl to give me money when they get there, that's over $1200 in tickets. And I just think it's horrible to ask ppl to buy a gift and pay to get in . My friend thinks ppl should pay for the admission too ($3) but again I think that's shitty. Or ppl can buy their own ticket, admission only or admission with rides when they get to the park, but again I'm just struggling with having ppl pay. 
Everyone seems really excited to have it at Lakeside bc we all love it there, and it is affordable. A friend had her shower at a bowling alley and I think everyone paid for their games. 
Any opinions would be great! Thanks!