Places are starting to think minors are bad for business because they’re more likely to cause disturbances (and often hang around without spending money)
A lot of these businesses are creating curfews for unaccompanied teens after around 2/3pm on Fridays and weekends, banning them on Fridays/weekends altogether, and/or banning them in the afternoon every day of the week (although some of the bans, like at the boardwalk, are after around 8pm). Some are banning them outright.
Another article less Philly centered
"They're being unruly, violating code of conduct, which can include running through the property in large groups, fighting and putting it on TikTok, basically disrupting business and making it uncomfortable for our everyday customers”
Quote from the general manager of the oldest mall in New Jersey
Widely used in the UK for a while