Yes it's safe. Most of the people there are in their teens and are there with just their friends or siblings so they should be fine. It's fine that they don't have skates because they are able to use the rentals which are included for use in the admittance price which I think is about $8.50 per person at the moment. I would say giving them about $15-20 like the person before said would be great but should be separate from the admittance fee money to make sure they've got enough.
Yes it is safe they will need at least 9 dollars each but I would send them off w $15-20 for emergencies or snacks
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