Social: Trading free tickets for Six Flags for money: Sin or not?

Hare Krishna!

I have a dilemma trading my privilege to let a few guest visit the park for money. Basically, I work for Six Flags and have this privilege that I can take any of my 2 guests to the park for a 1-day visit for free. I came across a couple who did not want to pay the full ticket price, but could pay about half to get inside the park. Obviously, I am not allowed to let people in for money, But in this case, I thought of making an exception because of the following reasoning:

Typically the guests that I take to the park are devotees who wouldn't otherwise buy tickets to visit the park -- so, taking them to the park is not really a loss for Six Flags. The couple in question are similar to them in that they would also not visit the park if they had to buy the ticket at full price.

So, while the material rule is that I should not let someone who is not a friend into the park, not all devotees that I let in are my friends (if you know what I mean -- many times I meet them for the first time at the park -- it's just 'seva'). So, from a spiritual perspective, would you consider taking that couple to the park for half the ticket price a sin -- especially if part of that money goes towards a donation to the temple?

Thanks,
Madhusudan Dasa

Afaik, nothing similar in dharma sastras, sorry. The golden rule is if you're worried about it (a suggestion from Paramatma) don't do it.