It could be perfectly innocent, but there are also unsavory and/or illegal things that go on at horse shows.
I rode saddleseat for a number of years, as a kid and as an adult, primarily due to availability of options. I showed a bit as an adult, and the bigger Saddlebred barns are generally going to be focused on getting the clients to show and spend money. I agree with others to look for something with more a broader outlook toward horsemanship, etc. As far as your investment, if you decide to look elsewhere, you can probably sell the show clothes, and your daughter can ride in the same boots and pants anywhere.
I did not have my own horse growing up - there was no money for that sort of thing. Looking back, I love that my I was able to experience a variety of horse-related activities. Starting out, I rode at a barn that was convenient, and then as I got older, I switched barns to try jumping.
There is nothing wrong with trying different barns in the area - see if thereâs something different that your daughter enjoys, or makes you more comfortable, or is better option cost-wise.
I am guessing your daughter is still fairly young, as she was in a lead line class? With it being summer now, there may be camp or day camp options? Look around, ask questions, call a local equine vet and ask if they have can provide any recommendations. If there is a tack shop in the area, visit or give them a call.